L9803

L9803 Super smart power motor driver with 8-Bit MCU, RAM, EEPROM, ADC, WDG, Timers, PWM and H-bridge driver Features ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ 6.4-18V Supply Operating Range 16 MHz Maximum Oscillator Frequency 8 MHz Maximum Internal Clock Frequency Oscillator Supervisor Fully Static operation -40°C to + 150°C Temperature Range User ROM: 16 Kbytes Data RAM: 256 bytes Data ROM: 128 bytes 64 pin HiQUAD64 package 10 multifunctional bidirectional I/O lines Two 16-bit Timers, each featuring: – 2 Input Captures – 2 Output Compares – External Clock input (on Timer 1) – PWM and Pulse Generator modes Two Programmable 16-bit PWM generator modules. CAN peripheral including Bus line interface according 2A/B passive specifications ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ HiQUAD64 10-bit Analog-to-Digital Converter Software Watchdog for system integrity Master Reset, Power-On Reset, Low Voltage Reset 90mΩ DMOS H-bridge. 8-bit Data Manipulation 63 basic Instructions and 17 main Addressing Modes 8 x 8 Unsigned Multiply Instruction True Bit Manipulation Complete Development Support on DOS/WINDOWSTM Real-Time Emulator Full Software Package on DOS/WINDOWS™ (C-Compiler, Cross-Assembler, Debugger). ■ ■ Order codes Part number L9803 Package HiQUAD64 Packing Tray June 2006 Rev 1 1/126 www.st.com 1 Contents L9803 Contents 1 General description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.1 1.2 1.3 1.4 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Pin out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Register & Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2 Central Processing Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.1 2.2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 CPU registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 3 Clocks, Reset, Interrupts & Power saving modes . . . . . . . . . . . . . . . . 18 3.1 Clock system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 3.1.1 3.1.2 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 External Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.2 3.3 Oscillator safeguard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 3.2.1 Dedicated Control Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Watchdog system (WDG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 3.3.1 3.3.2 3.3.3 3.3.4 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 3.4 3.5 Miscellaneous Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 3.5.1 3.5.2 3.5.3 3.5.4 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 External Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Reset Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Power-on Reset - Low Voltage Detection . . . . . . . . . . . . . . . . . . . . . . . 25 3.6 3.7 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Power Saving Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 3.7.1 3.7.2 3.7.3 3.7.4 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Slow Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Halt Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 2/126 L9803 Contents 4 Voltage Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 4.1 4.2 4.3 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 4.1.1 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Digital Section Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 4.2.1 VDD Short Circuit Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Analog Section Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 4.3.1 VCC Short Circuit Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 5 On-Chip Peripherals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 5.1 I/O Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 5.1.1 5.1.2 5.1.3 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 5.2 16-Bit Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 5.2.1 5.2.2 5.2.3 5.2.4 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 5.3 PWM Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 5.3.1 5.3.2 5.3.3 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 5.4 PWM I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 5.4.1 5.4.2 5.4.3 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 PWMO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 PWMI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 5.5 10-BIT A/D Converter (AD10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 5.5.1 5.5.2 5.5.3 5.5.4 5.5.5 5.5.6 5.5.7 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 Input Selections and Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 Interrupt Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 Temperature Sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 Precise Temperature Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 5.6 Controller Area Network (CAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 5.6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 3/126 Contents 5.6.2 5.6.3 5.6.4 L9803 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 5.7 CAN BUS TRANSCEIVER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 5.7.1 5.7.2 5.7.3 5.7.4 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 CAN Transceiver Disabling function . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 5.8 Power Bridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 5.8.1 5.8.2 5.8.3 5.8.4 5.8.5 5.8.6 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 Interrupt generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 5.9 EEPROM (EEP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 5.9.1 5.9.2 5.9.3 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 6 Instruction Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 6.1 6.2 ST7 Addressing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 Instruction groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111 7 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 7.1 7.2 7.3 7.4 7.5 7.6 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 Power considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 Application diagram example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117 DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 Control Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119 Operating block electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . 120 8 9 Package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 4/126 L9803 List of tables List of tables Table 1. Table 2. Table 3. Table 4. Table 5. Table 6. Table 7. Table 8. Table 9. Table 10. Table 11. Table 12. Table 13. Table 14. Table 15. Table 16. Table 17. Table 18. Table 19. Table 20. Table 21. Table 22. Table 23. Table 24. Table 25. Table 26. Table 27. Table 28. Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Recommended Values for 16 MHz Crystal Resonator . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Watchdog Timing (fOSC = 16 MHz) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Interrupt Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 I/O Port Mode Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 I/O Port Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Port A Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Port B Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Clock Control Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 16-Bit Timer Register Map and Reset Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 PWM Timing (fCPU = 8MHz) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 ADC Channel Selection Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 CAN Register Map and Reset Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Functional Description Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 ST7 Addressing Mode Overview: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 Absolute Maximum Ratings (Voltage Referenced to GND) . . . . . . . . . . . . . . . . . . . . . . . 114 Thermal Characteristics (VB=18V, TJ = 150°C, ILOAD = 2A) . . . . . . . . . . . . . . . . . . . . . 115 DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 Control Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119 A/D converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 POWER Bridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 PWM OUTPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 PWM INPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 Oscillator Safeguard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 CAN Transceiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 Power on/low voltage reset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 5/126 List of figures L9803 List of figures Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. Figure 9. Figure 10. Figure 11. Figure 12. Figure 13. Figure 14. Figure 15. Figure 16. Figure 17. Figure 18. Figure 19. Figure 20. Figure 21. Figure 22. Figure 23. Figure 24. Figure 25. Figure 26. Figure 27. Figure 28. Figure 29. Figure 30. Figure 31. Figure 32. Figure 33. Figure 34. Figure 35. Figure 36. Figure 37. Figure 38. Figure 39. Figure 40. Figure 41. Figure 42. Figure 43. Figure 44. Figure 45. Figure 46. Figure 47. Figure 48. L9803 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Pin out. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Organization of Internal CPU Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Stack Manipulation on Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 External Clock Source Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Crystal/Ceramic Resonator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Clock Prescaler Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Timing Diagram for Internal CPU Clock Frequency transitions . . . . . . . . . . . . . . . . . . . . . 20 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Power Up/Down behaviour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Reset Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Interrupt Processing Flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Wait Mode Flow Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Halt Mode Flow Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Voltage regulation block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 I/O Port General Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Interrupt I/O Port State Transitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Ports PA0-PA7, PB0-PB1I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Timer Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Counter Timing Diagram, internal clock divided by 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Counter Timing Diagram, internal clock divided by 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Counter Timing Diagram, internal clock divided by 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Input Capture Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Input Capture Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Output Compare Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Output Compare Timing Diagram, Internal Clock Divided by 2 . . . . . . . . . . . . . . . . . . . . . 49 One Pulse Mode Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 Pulse Width Modulation Mode Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 PWM Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 PWM Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 PWM Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 PWM I/O Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Impedance at PWMO/I pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 PWMI function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 Block diagram of the Analog to Digital Converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 Temperature Sensor output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 CAN Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 CAN Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 CAN Controller State Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 CAN Error State Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 Bit Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 CAN Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 Page Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Can Bus Transceiver Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 Power Bridge Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Example - Power Bridge Waveform, PWM Up Brake Driving Mode. . . . . . . . . . . . . . . . . . 99 EEPROM Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 Data EEPROM Programming Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 6/126 L9803 Figure 49. Figure 50. Figure 51. Figure 52. Figure 53. List of figures EEPROM Programming Flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 HiQUAD-64: qJA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 HiQUAD-64: Thermal impedance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 Application diagram example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117 HiQUAD-64 Mechanical Data & Package Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 7/126 General description L9803 1 1.1 General description Introduction The L9803 is a Super Smart Power device suited to drive resistive and inductive loads under software control. It includes a ST7 microcontroller and some pheripherals. The microcontroller can execute the software contained in the program ROM and drive, through dedicated registers, the power bridge. The internal voltage regulators rated to the automotive environment, PWM modules, CAN transceiver and controller, timers, temperature sensor and the AtoD converter allow the device to realize by itself a complete application, in line with the most common mechatronic requirements. 8/126 L9803 Figure 1. L9803 Block Diagram General description VB1 OSCIN OSCOUT OSC Internal CLOCK PREREGULATOR VB2 VDD OSC SAFEGUARD NRESET TM POWER SUPPLY VCC GND AGND VBR VBL POWER BRIDGE ADDRESS AND DATA BUS CONTROL 8-BIT CORE ALU ROM 16K RAM 256B OUTR OUTL PGND TEMP SENSOR EEPROM 128B AD2 10-bit ADC AD3 AD4 PWM 1 PWM 2 PWMO PWMI PORT B PB0 -> PB1 TIMER 2 PORT A TIMER 1 PA0 -> PA7 WATCHDOG CAN CONTROLLER RX CAN_H CAN_L TX CAN TRANSCEIVER PWMO PWMI 9/126 General description L9803 1.2 Figure 2. Pin out Pin out PA4/EXTCLK_1 PA5/OCMP2_2 PA6/OCMP1_2 PA2/ICAP2_1 PA3/ICAP1_1 PA7/ICAP2_2 PB0/ICAP1_2 AGND PGND NU NU NU AD3 AD2 PA1/OCMP1_1 PA0/OCMP2_1 TM VDD OSCIN OSCOUT GND NU VBL VBL VBL NU NU NU NU 64 63 62 61 60 59 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 PGND NU NU OUTL OUTL OUTL 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 27 28 29 30 31 32 PGND OUTR OUTR OUTR NU NU PGND VCC AD4 NU PB1/EXTCLK_2 NU NU PWMO PWMI NRESET CAN_H CAN_L GND VDD VB2 VB1 VBR VBR VBR NU NU NU NU 1.3 Pin Description AD2-AD4: Analog input to ADC. PA0/OCMP2_1-PA1/OCMP1_1: I/Os or Output compares on Timer 1. Alternate function software selectable (by setting OC2E or OC1E in CR2 register: bit 6 or 7 at 0031h). When used as an alternate function, this pin is a push-pull output as requested by Timer 1. Otherwise, this pin is a triggered floating input or a push-pull output. PA2/ICAP2_1-PA3/ICAP1_1: I/Os or Input captures on Timer 1. Before using this I/O as alternate inputs, they must be configured by software in input mode (DDR=0). In this case, these pins are a triggered floating input. Otherwise (I/O function), these pin are triggered floating inputs or push-pull outputs. PA4/EXTCLK_1: PA4 I/O or External Clock on Timer 1. Before using this I/O as alternate input, it must be configured by software in input mode (DDR=0). In this case, this pin is a triggered floating input. Otherwise (I/O function), this pin is a triggered floating input or a push-pull output. 10/126 L9803 General description PA5/OCMP2_2-PA6/OCMP1_2: I/Os or Output Compares on Timer 2. Alternate function software selectable (by setting OC2E or OC1E in CR2 register: bit 6 or 7 at 0041h). When used as alternate functions, these pins are push-pull outputs as requested by Timer 2. Otherwise, these pins are triggered floating inputs or push-pull outputs. PA7/ICAP2_2-PB0/ICAP1_2: I/Os or Input Captures on Timer 2. Before using these I/Os as alternate inputs, they must be configured by software in input mode (DDR=0). In this case, these pins are triggered floating inputs. Otherwise (I/O function), these pins are triggered floating inputs or push-pull outputs. PB1/EXTCLK_2: PB1 I/O or External Clock on Timer 2. Before using this I/O as alternate input, it must be configured by software in input mode (DDR=0). In this case, this pin is a triggered floating input. Otherwise (I/O function), this pin is a triggered floating input or a push-pull output. TM: Input. This pin must be held low during normal operating modes. VDD: Output. 5V Power supply for digital circuits, from internal voltage regulator. OSCIN: Input Oscillator pin. OSCOUT: Output Oscillator pin. GND: Ground for digital circuits. VBR: Power supply for Right half-bridge. OUTR: Output of Left half-bridge. PGND: Ground for power transistor. OUTL: Output of Right half-bridge. VBL: Power supply for Left half-bridge. VB1: Power supply for voltage regulators. VB2: Pre-regulated voltage for analog circuits. CAN_L: Low side CAN bus output. CAN_H: High side CAN bus input. NRESET: Bidirectional. This active low signal forces the initialization of the MCU. This event is the top priority non maskable interrupt. It can be used to reset external peripherals. PWMI: PWM input. Directly connected to Input Capture 2 on Timer 2. PWMO: PWM output. Connected to the output of PWM2 module. AGND: Ground for all analog circuitry (except power bridge). VCC: Output. 5V power supply for analog circuits, from internal voltage regulator. 1.4 Register & Memory Map As shown in the Table 1, the MCU is capable of addressing 64K bytes of memories and I/O registers. In this MCU, 63742 of these bytes are user accessible. The available memory locations consist of 128 bytes of I/O registers, 256 bytes of RAM, 128 bytes of EEPROM and 16Kbytes of user ROM. The RAM space includes 64bytes for the stack from 0140h to 017Fh. 11/126 General description The highest address bytes contain the user reset and interrupt vectors. Table 1. Address 0000h 0001h 0002h 0003h 0004h 0005h 0006h 0007h 0008h to 000Fh 0010h 0011h 0012h 0013h 0014h 0015h 0016h 0017h 0018h 0019h 001Ah 001Bh 001Ch 001Dh 001Eh 001Fh 0020h 0021h 0022h 0023h to 0029h 002Ah 002Bh 002Ch 002Dh 002Eh 002Fh 0030h WDG EEPROM WDGCR .. WDGSR .. EECR .. Power Bridge MISCR .. PBCSR .. DCSR .. P2CYRH .. P2CYRL .. P2DRH .. P2DRL .. P2CR .. P2CTH .. P2CTL .. P1CYRH .. P1CYRL .. P1DRH .. P1DRL .. P1CR .. P1CTH .. P1CTL .. L9803 Memory Map Block Register Label PADR .. PADDR .. PAOR .. PBDR .. PBDDR .. PBOR .. Register name Data Register Data Direction Register Option Register Not Used Data Register Data Direction Register Option Register Not Used RESERVED PWM1 Cycle Register High PWM1 Cycle Register Low PWM1 Duty Register High PWM1 Duty Register Low PWM1 Control Register PWM1 Counter Register High PWM1 Counter Register Low RESERVED PWM2 Cycle Register High PWM2 Cycle Register Low PWM2 Duty Register High PWM2 Duty Register Low PWM2 Control Register PWM2 Counter Register High PWM2 Counter Register Low RESERVED Miscellaneous Register Bridge Control Status Register Dedicated Control Status Register RESERVED Watchdog Control Register Watchdog Status Register EEPROM Control register RESERVED RESERVED 7Fh 00h 00h R/W R/W R/W 00h 00h 00h see Section 3.4 R/W R/W 00h 00h 00h 00h 00h 00h 00h R/W R/W R/W R/W R/W Read Only Read Only 00h 00h 00h 00h 00h 00h 00h R/W R/W R/W R/W R/W Read Only Read Only Reset Status 00h 00h 00h 00h 00h 00h Remarks R/W R/W R/W Absent R/W R/W R/W Absent Port A Port B PWM1 PWM2 12/126 L9803 Table 1. Address 0031h 0032h 0033h 0034h-0035h 0036h-0037h 0038h-0039h 003Ah-003Bh 003Ch-003Dh 003Eh-003Fh 0040h 0041h 0042h 0043h 0044h-0045h 0046h-0047h 0048h-0049h 004Ah-004Bh 004Ch-004Dh 004Eh-004Fh 0050h to 0059h 005Ah 005Bh 005Ch 005Dh 005Eh 005Fh 0060h to 006Fh CANISR .. CANICR .. CANCSR .. CANBRPR .. CANBTR .. CANPSR .. TIM2 T2CR2 .. T2CR1 .. T2SR .. T2IC1HR .. T2IC1LR .. T2OC1HR .. T2OC1LR .. T2CHR .. T2CLR .. T2ACHR .. T2ACLR .. T2IC2HR .. T2IC2LR .. T2OC2HR .. T2OC2LR .. TIM1 General description Memory Map (continued) Block Register Label T1CR2 .. T1CR1 .. T1SR .. T1IC1HR .. T1IC1LR .. T1OC1HR .. T1OC1LR .. T1CHR .. T1CLR .. T1ACHR .. T1ACLR .. T1IC2HR .. T1IC2LR .. T1OC2HR .. T1OC2LR .. Register name Timer 1 Control Register2 Timer 1 Control Register1 Timer 1 Status Register Timer 1 Input Capture1 High Register Timer 1 Input Capture1 Low Register Timer 1 Output Compare1 High Register Timer 1 Output Compare1 Low Register Timer 1 Counter High Register Timer 1 Counter Low Register Timer 1 Alternate Counter High Register Timer 1 Alternate Counter Low RegisteR Timer 1 Input Capture2 High Register Timer 1 Input Capture2 Low Register Timer 1 Output Compare2 High Register Timer 1 Output Compare2 Low Register Reserved: Write Forbidden Timer 2 Control Register2 Timer 2 Control Register1 Timer 2 Status Register Timer 2 Input Capture1 High Register Timer 2 Input Capture1 Low Register Timer 2 Output Compare1 High Register Timer 2 Output Compare1 Low Register Timer 2 Counter High Register Timer 2 Counter Low Register Timer 2 Alternate Counter High Register Timer 2 Alternate Counter Low Register Timer 2 Input Capture2 High Register Timer 2 Input Capture2 Low Register Timer 2 Output Compare2 High Register Timer 2 Output Compare2 Low Register RESERVED CAN Interrupt Status Register CAN Interrupt Control Register CAN Control/Status Register CAN Baud Rate Prescaler CAN Bit Timing Register CAN Page Selection CAN First address to last address of PAGE X 00h 00h 00h 00h 23h 00h -R/W R/W R/W R/W R/W R/W see page mapping and register description Read Only Read Only R/W 00h 00h xxh xxh xxh xxh xxh FFh FCh 00h 00h xxh xxh xxh xxh R/W R/W Read Only Read Only Read Only R/W R/W Read Only Read Only Read Only Read Only Read Only Read Only R/W R/W Reset Status 00h 00h xxh xxh xxh xxh xxh FFh FCh FFh FCh xxh xxh xxh xxh Remarks R/W R/W Read Only Read Only Read Only R/W R/W Read Only Read Only Read Only Read Only Read Only Read Only R/W R/W CAN 0070h 0071h 0072h ADC ADCDRH .. ADCDRL .. ADCCSR .. ADC Data Register High ADC Data Register Low ADC Control/Status Register 00h 00h 20h 13/126 General description L9803 Address 0080h to 013Fh 0140h to 017Fh 0180h to 0BFFh Block RAM 256 Bytes including STACK 64 bytes (0140h to 017Fh) Description User variables and subroutine nesting RESERVED including 4 bytes reserved for temperature sensor trimming (see Section 5.5.6) 0C7CH: T0H 0C7DH: T0L 0C7EH: VT0H 0C7FH: VT0L RESERVED User application code and data Interrupt and Reset Vectors 0C00h to 0C7Fh EEPROM 128 bytes 0C80h to BFFFh C000 to FFDFh FFE0h to FFFFh ROM 16K bytes (16384 bytes) 14/126 L9803 Central Processing Unit 2 2.1 Central Processing Unit Introduction The CPU has a full 8-bit architecture. Six internal registers allow efficient 8-bit data manipulation. The CPU is capable of executing 63 basic instructions and features 17 main addressing modes. 2.2 CPU registers The 6 CPU registers are shown in the programming model in Figure 3. Following an interrupt, all registers except Y are pushed onto the stack in the order shown in Figure 4. They are popped from stack in the reverse order. The Y register is not affected by these automatic procedures. The interrupt routine must therefore handle Y, if needed, through the PUSH and POP instructions. Accumulator (A). The Accumulator is an 8-bit general purpose register used to hold operands and the results of the arithmetic and logic calculations as well as data manipulations. Index Registers (X and Y). These 8-bit registers are used to create effective addresses or as temporary storage areas for data manipulation. The Cross-Assembler generates a PRECEDE instruction (PRE) to indicate that the following instruction refers to the Y register. Program Counter (PC). The program counter is a 16-bit register containing the address of the next instruction to be executed by the CPU. Figure 3. Organization of Internal CPU Registers 7 ACCUMULATOR: 0 RESET VALUE: XXXXXXXX 7 0 X INDEX REGISTER: RESET VALUE: XXXXXXXX 7 0 Y INDEX REGISTER: RESET VALUE: XXXXXXXX 15 7 0 PROGRAM COUNTER: RESET VALUE = RESET VECTOR @ FFFEh-FFFFh 15 STACK POINTER: 00000001 RESET VALUE =0 0 0 0 0 0 0 1 0 1 1 1 1 1 1 1 7 CONDITION CODE REGISTER: X = Undefined 111HI 0 NZC 7 0 RESET VALUE: 111X1XXX 15/126 Central Processing Unit L9803 Stack Pointer (SP) The Stack Pointer is a 16-bit register. Since the stack is 64 bytes deep, the most significant bits are forced as indicated in Figure 3 in order to address the stack as it is mapped in memory. Following an MCU Reset, or after a Reset Stack Pointer instruction (RSP), the Stack Pointer is set to point to the next free location in the stack. It is then decremented after data has been pushed onto the stack and incremented before data is popped from the stack. Note: When the lower limit is exceeded, the Stack Pointer wraps around to the stack upper limit, without indicating the stack overflow. The previously stored information is then overwritten and therefore lost. The upper and lower limits of the stack area are shown in the Memory Map. The stack is used to save the CPU context during subroutine calls or interrupts. The user may also directly manipulate the stack by means of the PUSH and POP instructions. In the case of an interrupt (refer to Figure 4), the PCL is stored at the first location pointed to by the SP. Then the other registers are stored in the next locations. When an interrupt is received, the SP is decremented and the context is pushed on the stack. On return from interrupt, the SP is incremented and the context is popped from the stack. A subroutine call occupies two locations and an interrupt five locations in the stack area. Condition Code Register (CC) The Condition Code register is a 5-bit register which indicates the result of the instruction just executed as well as the state of the processor. These bits can be individually tested by a program and specified action taken as a result of their state. The following paragraphs describe each bit of the CC register in turn. Half carry bit (H) The H bit is set to 1 when a carry occurs between bits 3 and 4 of the ALU during an ADD or ADC instruction. The H bit is useful in BCD arithmetic subroutines. Interrupt mask (I) When the I bit is set to 1, all interrupts except the TRAP software interrupt are disabled. Clearing this bit enables interrupts to be passed to the processor core. Interrupts requested while I is set are latched and can be processed when I is cleared (only one interrupt request per interrupt enable flag can be latched). Negative (N) When set to 1, this bit indicates that the result of the last arithmetic, logical or data manipulation is negative (i.e. the most significant bit is a logic 1). Zero (Z) When set to 1, this bit indicates that the result of the last arithmetic, logical or data manipulation is zero. Carry/Borrow (C) When set, C indicates that a carry or borrow out of the ALU occured during the last arithmetic operation. This bit is also affected during execution of bit test, branch, shift, rotate and store instructions. 16/126 L9803 Figure 4. Stack Manipulation on Interrupt Central Processing Unit CONTEXT SAVED ON INTERRUPT 7 1 1 1 CONDITION CODE 0 LOWER ADDRESS ACCUMULATOR X INDEX REGISTER PCH PCL CONTEXT RESTORED ON RETURN HIGHER ADDRESS 17/126 Clocks, Reset, Interrupts & Power saving modes L9803 3 3.1 3.1.1 Clocks, Reset, Interrupts & Power saving modes Clock system General Description The MCU accepts either a Crystal or Ceramic resonator, or an external clock signal to drive the internal oscillator. The internal clock (fCPU) is derived from the external oscillator frequency (fOSC). The external Oscillator clock is first divided by 2, and an additional division factor of 2, 4, 8, or 16 can be applied, in Slow Mode, to reduce the frequency of the fCPU; this clock signal is also routed to the on-chip peripherals (except the CAN). The CPU clock signal consists of a square wave with a duty cycle of 50%. The internal oscillator is designed to operate with an AT-cut parallel resonant quartz crystal resonator in the frequency range specified for fosc. The circuit shown in Figure 6 is recommended when using a crystal, and Table 2 lists the recommended capacitance and feedback resistance values. The crystal and associated components should be mounted as close as possible to the input pins in order to minimize output distortion and start-up stabilisation time. Use of an external CMOS oscillator is recommended when crystals outside the specified frequency ranges are to be used. Table 2. Recommended Values for 16 MHz Crystal Resonator RSMAX COSCIN COSCOUT RP 40 Ω 56pF 56pF 1-10 MΩ 60 Ω 47pF 47pF 1-10 MΩ 150 Ω 22pF 22pF 1-10 MΩ Note: RSMAX is the equivalent serial resistor of the crystal (see crystal specification). COSCIN,COSCOUT: Maximum total capacitances on pins OSCIN and OSCOUT (the value includes the external capacitance tied to the pin plus the parasitic capacitance of the board and of the device). Rp: External shunt resistance. Recommended value for oscillator stability is 1MΩ. Figure 5. External Clock Source Connections OSCin OSCout NC EXTERNAL CLOCK 18/126 L9803 Figure 6. Clocks, Reset, Interrupts & Power saving modes Crystal/Ceramic Resonator OSCin RP OSCout COSCin COSCout Figure 7. Clock Prescaler Block Diagram %2 OSCin OSCout RP %2,4,8,16 CPUCLK to CPU and Peripherals to CAN COSCin COSCout 3.1.2 External Clock An external clock may be applied to the OSCIN input with the OSCOUT pin not connected, as shown on Figure 5. The tOXOV specifications does not apply when using an external clock input. The equivalent specification of the external clock source should be used instead of tOXOV . 19/126 Clocks, Reset, Interrupts & Power saving modes Figure 8. Timing Diagram for Internal CPU Clock Frequency transitions L9803 OSC/2 OSC/4 OSC/8 CPU CLK b1 : b2 00 01 MISCELLANEOUS REGISTER b0 1 1 0 New frequency requested New frequency active when osc/4 & osc/8 = 0 Normal mode requested Normal mode active (osc/4 - osc/8 stopped) VR02062B 3.2 Oscillator safeguard The L9803 contains an oscillator safe guard function. This function provides a real time check of the crystal oscillator generating a reset condition when the clock frequency has anomalous value. If fOSCfhigh, a reset is generated. A flag in the Dedicated Control Status Register indicates if the last reset is a safeguard reset. At the output of reset state the safeguard is disable. To activate the safeguard SFGEN bit must be set. Note: Following a reset, the safeguard is disabled. Once activated it cannot be disabled, except by a reset. 3.2.1 Dedicated Control Status Register DCSR Address 0022h - Read/Write Reset Value:xx00 0000 (00h) SGFL SGFH SFGEN CANDS b3 b2 b1 PIEN b6 = SGFH: Safeguard high flag. Set by an Oscillator Safeguard Reset generated for frequency too high, cleared by software (writing zero) or Power On / Low Voltage Reset. 20/126 L9803 Clocks, Reset, Interrupts & Power saving modes This flag is useful for distinguishing Safeguard Reset, Power On / Low Voltage Reset and Watchdog Reset. b7 = SGFL: Safeguard low flag. Set by an Oscillator Safeguard Reset generated for frequency too low, cleared by software (writing zero) or Power On / Low Voltage Reset. This flag is useful for distinguishing Safeguard Reset, Power On / Low Voltage Reset and Watchdog Reset. b5 = SFGEN: Safeguard enable when set. It’s cleared only by hardware after a reset. b4 = CANDS: CAN Transceiver disable. When this bit is set the CAN transceiver goes in Power Down Mode and does not work until this bit is reset. CANDS is 0 after reset so the standard condition is with the transceiver enabled. This bit can be used by application requiring low power consumption (see Section 5.8 for details). b3,b2,b1 = not used b0 = PIEN: PWMI input enable. When set, the PWMI input line is connected to Input Capture 2 of Timer 2. Otherwise, ICAP2_2 is the alternate function of PA7. See Figure 34 for the explanation of this function. 3.3 3.3.1 Watchdog system (WDG) Introduction The Watchdog is used to detect the occurrence of a software fault, usually generated by external interference or by unforeseen logical conditions, which causes the application program to give up its normal sequence. The Watchdog circuit generates an MCU reset on expiry of a programmed time period, unless the program refreshes the counter’s contents before it is decremented to zero. 3.3.2 Main Features – – – – Programmable Timer (64 increments of 12,288 CPU clock) Programmable Reset reset (if watchdog activated) after an HALT instruction or when bit timer MSB reaches zero Watchdog Reset indicated by status flag. 3.3.3 Functional Description The counter value stored in the CR register (bits T6:T0), is decremented every 12,288 machine cycles, and the length of the timeout period can be programmed by the user in 64 increments. If the watchdog is activated (the WDGA bit is set) and when the 7-bit timer (bits T6:T0) rolls over from 40h to 3Fh (T6 becomes cleared), it initiates a reset cycle pulling low the reset pin for typically 500ns. 21/126 Clocks, Reset, Interrupts & Power saving modes L9803 The application program must write in the CR register at regular intervals during normal operation to prevent an MCU reset. The value to be stored in the CR register must be between FFh and C0h (see Table 1): – – – The WDGA bit is set (watchdog enabled) The T6 bit is set to prevent generating an immediate reset The T5:T0 bit contain the number of increments which represents the time delay before the watchdog produces a reset. Watchdog Timing (fOSC = 16 MHz) WDG Register initial value FFh C0h WDG timeout period (ms) 98.3 1.54 Table 3. Note: Following a reset, the watchdog is disabled. Once activated it cannot be disabled, except by a reset. The T6 bit can be used to generate a software reset (the WDGA bit is set and the T6 bit is cleared). If the watchdog is activated, the HALT instruction will generate a Reset. Figure 9. Functional Description WATCHDOG STATUS REGISTER (WDGSR) RESET WDGF WATCHDOG CONTROL REGISTER (WDGCR) WDGA MSB 7-BIT DOWNCOUNTER LSB fCPU CLOCK DIVIDER ÷12288 The Watchdog delay time is defined by bits 5-0 of the Watchdog register; bit 6 must always be set in order to avoid generating an immediate reset. Conversely, this can be used to generate a software reset (bit 7 = 1, bit 6 = 0). The Watchdog must be reloaded before bit 6 is decremented to “0” to avoid a Reset. Following a Reset, the Watchdog register will contain 7Fh (bits 0-7). If the circuit is not used as a Watchdog (i.e. bit 7 is never set), bits 6 to 0 may be used as a simple 7-bit timer, for instance as a real time clock. Since no reset will be generated under these conditions, the Watchdog control register must be monitored by software. 22/126 L9803 Clocks, Reset, Interrupts & Power saving modes A flag in the watchdog status register indicates if the last reset is a watchdog reset or not, before clearing by a write of this register. 3.3.4 Register Description Watchdog Control Register (WDGCR) Register Address: 002Ah 7 WDGA T6 T5 T4 T3 T2 T1 — Read/Write 0 T0 Reset Value: 0111 1111 (7Fh) b7 = WDGA: Activation bit. This bit is set by software and only cleared by hardware after a reset. When WDGA = 1, the watchdog can generate a reset. 0: Watchdog disabled 1: Watchdog enabled. b6-0 =T6-T0: 7 bit timer (Msb to Lsb) These bits contain the decremented value. A reset is produced when it rolls over from 40h to 3Fh (T6 become cleared). Watchdog Status Register (WDGSR) Register Address: 002Bh (*) — Read/Write Reset Value : 0000 0000 (00h) 7 0 WDGF b7-1 = not used b0 = WDGF: Watchdog flag. Set by a Watchdog Reset, cleared by software (writing zero) or Power On / Low Voltage Reset. This flag is useful for distinguishing Power On / Low Voltage Reset and Watchdog Reset. (*): Except in the case of Watchdog Reset. 3.4 Miscellaneous Register (MISCR) The Miscellaneous register allows the user to select the Slow operating mode and to set the clock division prescaler factor. Bits 3, 4 determine the signal conditions which will trigger an interrupt request on I/O pins having interrupt capability. Register Address: 0020h — Read/Write 23/126 Clocks, Reset, Interrupts & Power saving modes Reset Value:0000 0000 (00h) b4 b3 b2 b1 L9803 b0 b0 - Slow Mode Select 0- Normal mode - Oscillator frequency / 2 (Reset state) 1- Slow mode (Bits b1 and b2 define the prescaler factor) b1, b2 - CPU clock prescaler for Slow Mode b2 0 1 0 1 b1 0 0 1 1 Oscillator frequency / 4 Oscillator frequency / 8 Oscillator frequency / 16 Oscillator frequency / 32 Option b3, b4 - External Interrupt Option b4 0 1 0 1 b3 0 0 1 1 Option Falling edge and low level (Reset state) Falling edge only Rising edge only Rising and Falling edge The selection issued from b3/b4 combination is applied to PA[0]..PA[7],PB0,PB1 external interrupt. The selection can be made only if I bit in CC register is reset (interrupt enabled). b3, b4 can be written only when the Interrupt Mask (I) of the CC (Condition Code) register is set to 1. b5,b6,b7 = not used 3.5 3.5.1 Reset Introduction There are four sources of Reset: – – – – NRESET pin (external source) Power-On Reset / Low Voltage Detection (Internal source) WATCHDOG (Internal Source) SAFEGUARD (Internal source) The Reset Service Routine vector is located at address FFFEh-FFFFh. 24/126 L9803 Clocks, Reset, Interrupts & Power saving modes 3.5.2 External Reset The NRESET pin is both an input and an open-drain output with integrated pull-up resistor. When one of the internal Reset sources is active, the Reset pin is driven low to reset the whole application. 3.5.3 Reset Operation The duration of the Reset condition, which is also reflected on the output pin, is fixed at 4096 internal CPU Clock cycles. A Reset signal originating from an external source must have a duration of at least 1.5 internal CPU Clock cycles in order to be recognised. At the end of the Power-On Reset cycle, the MCU may be held in the Reset condition by an External Reset signal. The NRESET pin may thus be used to ensure VDD has risen to a point where the MCU can operate correctly before the user program is run. Following a Power-On Reset event, or after exiting Halt mode, a 4096 CPU Clock cycle delay period is initiated in order to allow the oscillator to stabilise and to ensure that recovery has taken place from the Reset state. During the Reset cycle, the device Reset pin acts as an output that is pulsed low. In its high state, an internal pull-up resistor of about 300KΩ is connected to the Reset pin. This resistor can be pulled low by external circuitry to reset the device. 3.5.4 Power-on Reset - Low Voltage Detection The POR/LVD function generates a static reset when the supply voltage is below a reference value. In this way, the Power-On Reset and Low Voltage Reset function are provided, in order to keep the system in safe condition when the voltage is too low. The Power-Up and Power-Down thresholds are different, in order to avoid spurious reset when the MCU starts running and sinks current from the supply. The LVD reset circuitry generates a reset when VDD is below: – – VResetON when VDD is rising VResetOFF when VDD is falling The POR/LVD function is explained in Figure 11. Power-On Reset activates the reset pull up transistor performing a complete chip reset. In the same way a reset can be triggered by the watchdog, by the safeguard or by external low level at NRESET pin. An external capacitor connected between NRESET and ground can extend the power on reset period if required. 25/126 Clocks, Reset, Interrupts & Power saving modes Figure 10. Power Up/Down behaviour VDD L9803 5V VReset ON VReset OFF VReset UD t POR/LVD 5V = undefined value t Figure 11. Reset Block Diagram VDD 300K to ST7 Counter Oscillator Signal CLK Internal RESET RESET NRESET Reset Watchdog Reset Safeguard Reset POR/LVD Reset 26/126 L9803 Clocks, Reset, Interrupts & Power saving modes 3.6 Interrupts A list of interrupt sources is given in Table 4 below, together with relevant details for each source. Interrupts are serviced according to their order of priority, starting with I0, which has the highest priority, and so to I12, which has the lowest priority. The following list describes the origins for each interrupt level: – – – – – – – – – – – – – I0 connected to Ports PA0-PA7, PB0-PB1 I1 connected to CAN I2 connected to Power Diagnostics I3 connected to Output Compare of Timer 1 I4 connected to Input Capture of TImer 1 I5 connected to Timer 1 Overflow I6 connected to Output Compare of Timer 2 I7 connected to Input Capture of TImer 2 I8 connected to Timer 2 Overflow I9 connected to ADC End Of Conversion I10 connected to PWM 1 Overflow I11 connected to PWM 2 Overflow I12 connected to EEPROM Exit from Halt mode may only be triggered by an External Interrupt on one of the following ports: PA0-PA7 (I0), PB0-PB1 (I0), or by an Internal Interrupt coming from CAN peripheral (I1). If more than one input pin of a group connected to the same interrupt line are selected simultaneously, the OR of this signals generates the interrupt. Table 4. Interrupt Mapping Interrupts Reset Software Ext. Interrupt (Ports PA0-PA7, PB0PB1) Receive Interrupt Flag Transmit Interrupt Flag Error Interrupt Pending Power Bridge Short Circuit Overtemperature Output Compare 1 Timer 1 Status Output Compare 2 Input Capture 1 Timer 1 Status Input Capture 2 ICF2_1 OCF2_1 ICF1_1 I4 FFF2h-FFF3h Bridge Control Status CAN Status Register N/A N/A N/A Flag name N/A N/A N/A RXIFi TXIF EPND SC I2 OVT OCF1_1 I3 FFF4h-FFF5h FFF6h-FFF7h I1 FFF8h-FFF9h Interrupt source I0 Vector Address FFFEh-FFFFh FFFCh-FFFDh FFFAh-FFFBh 27/126 Clocks, Reset, Interrupts & Power saving modes Table 4. Interrupt Mapping (continued) Interrupts Timer Overflow Output Compare 1 Timer 2 Status Output Compare 2 Input Capture 1 Timer 2 Status Input Capture 2 Timer Overflow ADC End Of Conversion PWM 1 Overflow PWM 2 Overflow EEPROM Programming Timer 2 Status ADC Control N/A N/A EEPROM Control ICF2_2 TOF_2 EOC N/A N/A E2ITE I8 I9 I10 I11 I12 OCF2_2 ICF1_2 I7 Register Timer 1 Status Flag name TOF_1 OCF1_2 I6 Interrupt source I5 L9803 Vector Address FFF0h-FFF1h FFEEh-FFEFh FFECh-FFEDh FFEAh-FFEBh FFE8h-FFE9h FFE6h-FFE7h FFE4h-FFE5h FFE2h-FFE3h Figure 12. Interrupt Processing Flowchart INTERRUPT Y TRAP Y I BIT = 1 N PUSH PC,X,A,CC ONTO STACK SET I BIT TO 1 FETCH NEXT INSTRUCTION OF APPROPRIATE INTERRUPT SERVICE ROUTINE LOAD PC WUTH APPROPRIATE INTERRUPT VECTOR (1) EXECUTE INSTRUCTION Note: 1 See Table 4 28/126 L9803 Clocks, Reset, Interrupts & Power saving modes 3.7 3.7.1 Power Saving Modes Introduction There are three Power Saving modes. The Slow Mode may be selected by setting the relevant bits in the Miscellaneous register as detailed in Section 3.4. Wait and Halt modes may be entered using the WFI and HALT instructions. 3.7.2 Slow Mode In Slow mode, the oscillator frequency can be divided by 4, 8, 16 or 32 rather than by 2. The CPU and peripherals (except CAN, see Note) are clocked at this lower frequency. Slow mode is used to reduce power consumption. Note: Before entering Slow mode and to guarantee low power operations, the CAN Controller must be placed by software in STANDBY mode. 3.7.3 Wait Mode Wait mode places the MCU in a low power consumption mode by stopping the CPU. All peripherals remain active. During Wait mode, the I bit (CC Register) is cleared, so as to enable all interrupts. All other registers and memory remain unchanged. The MCU will remain in Wait mode until an Interrupt or Reset occurs, whereupon the Program Counter branches to the starting address of the Interrupt or Reset Service Routine. The MCU will remain in Wait mode until a Reset or an Interrupt (coming from CAN, Timers 1 & 2, EEPROM, ADC, PWM 1 & 2, I/O ports peripherals and Power Bridge) occurs, causing its wake-up. Refer to Figure 12 below. Figure 13. Wait Mode Flow Chart WAIT INSTRUCTION OSCILLATOR PERIPH. CLOCK CPU CLOCK I-BIT ON ON OFF CLEARED N N RESET Y INTERRUPT Y OSCILLATOR PERIPH. CLOCK CPU CLOCK I-BIT ON ON ON SET FETCH RESET VECTOR OR SERVICE INTERRUPT 29/126 Clocks, Reset, Interrupts & Power saving modes L9803 3.7.4 Halt Mode The Halt mode is the MCU lowest power consumption mode. The Halt mode is entered by executing the HALT instruction. The internal oscillator is then turned off, causing all internal processing to be stopped, including the operation of the on-chip peripherals. When entering Halt mode, the I bit in the CC Register is cleared so as to enable External Interrupts. If an interrupt occurs, the CPU becomes active. The MCU can exit the Halt mode upon reception of either an external interrupt (I0), a internal interrupt coming from the CAN peripheral (I1) or a reset. The oscillator is then turned on and a stabilisation time is provided before releasing CPU operation. The stabilisation time is 4096 CPU clock cycles. After the start up delay, the CPU continues operation by servicing the interrupt which wakes it up or by fetching the reset vector if a reset wakes it up. Note: The Halt mode cannot be used when the watchdog or the Safeguard are enabled, if the HALT instruction is executed while the watchdog or safeguard system are enabled, a reset is automatically generated thus resetting the entire MCU. Halt Mode affects only the digital section of the device. All the analog circuit remain in their status, including ADC, voltage regulators, bus transceivers and power bridge. Figure 14. Halt Mode Flow Chart HALT INSTRUCTION OSCILLATOR PERIPH. CLOCK CPU CLOCK I-BIT OFF OFF OFF CLEARED N N EXTERNAL INTERRUPT Y RESET Y OSCILLATOR PERIPH. CLOCK CPU CLOCK I-BIT ON ON ON SET 4096 CPU CLOCK CYCLES DELAY FETCH RESET VECTOR OR SERVICE INTERRUPT 30/126 L9803 Voltage Regulator 4 4.1 Voltage Regulator Introduction The on chip voltage regulator provides two regulated voltage, nominally 5V both. VCC supplies ADC and the analog periphery and VDD supplies the microcontroller and logic parts. These voltage are available at pins VDD and VCC to supply external components and connects a capacitors to optimize EMI performance. A pre-regulator circuit allows to connect external tantalum capacitors to a lower (10V) voltage (VB2 pin). 4.1.1 Functional Description The main supply voltage is taken from VB1 pin. A voltage pre-regulator provides the regulated voltage on pin VB2. VB2 is the supply for the digital and analog regulators. The block diagram shows the connections between the regulators and the external pins. In order to prevent negative spikes on the battery line to propagate on the internal supply generating spurious reset, a series diode supply VB1 pin is recommended. Figure 15. Voltage regulation block diagram PRE-REGULATOR Battery VB1 VB2 ANALOG VOLTAGE REGULATOR force sense VCC ADC AGND DIGITAL VOLTAGE REGULATOR VDD GND 31/126 Voltage Regulator L9803 4.2 Digital Section Power Supply The digital supply voltage VDD is available at pin number 42 and 9. The digital ground GND is available at pin number 43 and 12. Pin 42 and 43 are the actual voltage regulator output and external loads must be supply by these pin. The 100nF compensation capacitor should be connected as close as possible to pin 42 and 43. Pin number 9 and 12 provide an external access to the internal oscillator supply. Resonator’s capacitors should be grounded on pin 12. The application board can improve noise reduction in the chip connecting directly pin 42 to pin 9 and pin 43 to pin 12 using traces as short as possible. An additional capacitor mounted close to pin 9 and 12 can lead additional improvement. 4.2.1 VDD Short Circuit Protection The output current of the digital voltage regulator is controlled by a circuit that limits it to a maximum value (IMAXVDD). When the output current exceeds this value the VDD voltage starts falling down. External loads must be chosen taking in account this maximum current capability of the regulator. 4.3 Analog Section Power Supply The analog supply voltage is available on VCC pin. The external 100nF compensation capacitor should be placed as close as possible to this pin and AGND pin. VCC is the reference voltage for the AD conversion and must be used to supply ratiometric sensors feeding AD inputs. Any voltage drop between VCC pin and the sensor supply pin on the application board, will cause the ADC to be inaccurate when reading the sensor’s output. 4.3.1 VCC Short Circuit Protection The output current of the analog voltage regulator is controlled by a circuit that limits it to a maximum value (IMAXVCC). When the output current exceeds this value the VCC voltage starts falling down. External loads must be chosen taking in account this maximum current capability of the regulator. Warning: The pin VB2 is not short circuit protected so a short circuit on this pin will destroy the device. 32/126 L9803 On-Chip Peripherals 5 5.1 5.1.1 On-Chip Peripherals I/O Ports Introduction The internal I/O ports allow the transfer of data through digital inputs and outputs, the interrupt generation coming from an I/O and for specific pins, the input/output of alternate signals for the on-chip peripherals (TIMERS...). Each pin can be programmed independently as digital input (with or without interrupt generation) or digital output. 5.1.2 Functional Description Each port has 2 main registers: – – – Data Register (DR) Data Direction Register (DDR) Option Register (OR) and one optional register: Each I/O pin may be programmed using the corresponding register bits in the DDR and OR registers: bit X corresponding to pin X of the port. The same correspondence is used for the DR register. The following description takes into account the OR register, (for specific ports which do not provide this register refer to the I/O Port Implementation section). The generic I/O block diagram is shown in Figure 16. Input Modes The input configuration is selected by clearing the corresponding DDR register bit. In this case, reading the DR register returns the digital value applied to the external I/O pin. Different input modes can be selected by software through the OR register. Note: 1 2 3 1. Writing the DR register modifies the latch value but does not affect the pin status. 2. When switching from input to output mode, the DR register has to be written first to drive the correct level on the pin as soon as the port is configured as an output. 3. Do not use read/modify/write instructions (BSET or BRES) to modify the DR register External interrupt function When an I/O is configured as Input with Interrupt, an event on this I/O can generate an external interrupt request to the CPU. Each pin can independently generate an interrupt request. The interrupt sensitivity is independently programmable using the sensitivity bits in the Miscellaneous register. Each external interrupt vector is linked to a dedicated group of I/O port pins (see pinout description and interrupt section). If several input pins are selected simultaneously as interrupt source, these are logically NANDed. For this reason if one of the interrupt pins is tied low, it masks the other ones. 33/126 On-Chip Peripherals L9803 In case of a floating input with interrupt configuration, special care must be taken when changing the configuration (see Figure 17). The external interrupts are hardware interrupts, which means that the request latch (not accessible directly by the application) is automatically cleared when the corresponding interrupt vector is fetched. To clear an unwanted pending interrupt by software, the sensitivity bits in the Miscellaneous register must be modified. Output Mode The output configuration is selected by setting the corresponding DDR register bit. In this case, writing the DR register applies this digital value to the I/O pin through the latch. Then reading the DR register returns the previously stored value. Two different output modes can be selected by software through the OR register: Output push-pull and open-drain. DR register value and output pin status: DR 0 1 Push-Pull Vss VDD Open-drain Vss Floating Alternate function When an on-chip peripheral is configured to use a pin, the alternate function is automatically selected. This alternate function takes priority over the standard I/O programming. When the signal is coming from an on-chip peripheral, the I/O pin is automatically configured in output mode (push-pull or open drain according to the peripheral). When the signal is going to an on-chip peripheral, the I/O pin must be configured in input mode. In this case, the pin state is also digitally readable by addressing the DR register. Note: Input pull-up configuration can cause unexpected value at the input of the alternate peripheral input. When an on-chip peripheral use a pin as input and output, this pin has to be configured in input floating mode. 34/126 L9803 Figure 16. I/O Port General Block Diagram REGISTER ACCESS ALTERNATE OUTPUT 1 VDD 0 ALTERNATE ENABLE DR On-Chip Peripherals P-BUFFER (see table below) PULL-UP (see table below) VDD DDR PULL-UP CONFIGURATION If implemented OR SEL N-BUFFER DDR SEL CMOS SCHMITT TRIGGER ANALOG INPUT DIODES (see table below) PAD OR EXTERNAL INTERRUPT SOURCE (eix) Table 5. Input Pull-up with/without Interrupt Push-pull Off Output Open Drain (logic level) True Open Drain NI On Legend: DATA BUS DR SEL 1 0 ALTERNATE INPUT FROM OTHER BITS POLARITY SELECTION I/O Port Mode Options Diodes Configuration Mode Floating with/without Interrupt Pull-Up Off Off On On Off NI NI (see note) On P-Buffer to VDD to VSS NI - not implemented Off - implemented not activated On - implemented and activated Note: The diode to VDD is not implemented in the true open drain pads. A local protection between the pad and VSS is implemented to protect the device against positive stress. 35/126 On-Chip Peripherals Table 6. I/O Port Configurations Hardware Configuration NOT IMPLEMENTED IN TRUE OPEN DRAIN I/O PORTS VDD RPU PAD PULL-UP CONFIGURATION DR REGISTER ACCESS L9803 DR REGISTER W DATA BUS R INPUT 1) ALTERNATE INPUT FROM OTHER PINS INTERRUPT CONFIGURATION POLARITY SELECTION ANALOG INPUT NOT IMPLEMENTED IN TRUE OPEN DRAIN I/O PORTS EXTERNAL INTERRUPT SOURCE (eix) OPEN-DRAIN OUTPUT 2) VDD RPU DR REGISTER ACCESS PAD DR REGISTER R/W DATA BUS ALTERNATE ENABLE ALTERNATE OUTPUT PUSH-PULL OUTPUT 2) NOT IMPLEMENTED IN TRUE OPEN DRAIN I/O PORTS VDD RPU DR REGISTER ACCESS PAD DR REGISTER R/W DATA BUS ALTERNATE ENABLE ALTERNATE OUTPUT Note: 1 2 1. When the I/O port is in input configuration and the associated alternate function is enabled as an output, reading the DR register will read the alternate function output status. 2. When the I/O port is in output configuration and the associated alternate function is enabled as an input, the alternate function reads the pin status given by the DR register content. The alternate function must not be activated as long as the pin is configured as input with interrupt, in order to avoid generating spurious interrupts. Caution: Warning: The analog input voltage level must be within the limits stated in the absolute maximum ratings. The hardware implementation on each I/O port depends on the settings in the DDR and OR registers and specific feature of the I/O port.Switching these I/O ports from one state to another should be done in a sequence that prevents unwanted side effects. Recommended safe transitions are illustrated in Figure 17. Other transitions are potentially risky and should 36/126 L9803 On-Chip Peripherals be avoided, since they are likely to present unwanted side-effects such as spurious interrupt generation. Figure 17. Interrupt I/O Port State Transitions 01 INPUT floating/pull-up interrupt 00 INPUT floating (reset state) 10 OUTPUT open-drain 11 OUTPUT push-pull XX = DDR, OR I/O Port Implementation The I/O port register configurations are resumed as following. Port PA(7:0), Port PB(2:0) DDR 0 0 1 1 OR 0 1 0 1 MODE input no interrupt (pull-up enabled) input interrupt (pull-up enabled) Open-Drain output Push-Pull output RESET status: DR=0, DDR=0 and OR=0 (Input mode, no interrupt). These ports offer interrupt capabilities. 37/126 On-Chip Peripherals L9803 Dedicated Configurations Table 7. PORT A Input PA0 PA1 PA2 PA3 PA4 PA5 PA6 PA7 triggered with pull-up triggered with pull-up triggered with pull-up triggered with pull-up triggered with pull-up triggered with pull-up triggered with pull-up triggered with pull-up Output push-pull/open drain push-pull/open drain push-pull/open drain push-pull/open drain push-pull/open drain push-pull/open drain push-pull/open drain push-pull/open drain Alternate OCMP2_1: Output Compare #2 Timer 1 OCMP1_1: Output Compare #1 Timer 1 ICAP2_1: Input Capture #2 Timer 1 ICAP1_1: Input Capture #1 Timer 1 EXTCLK_1: External Clock Timer 1 OCMP2_2: Output Compare #2 Timer 2 OCMP1_2: Output Compare #1 Timer 2 ICAP2_2: Input Capture #2 Timer 2 Interrupt wake-up interrupt (I0) wake-up interrupt (I0) wake-up interrupt (I0) wake-up interrupt (I0) wake-up interrupt (I0) wake-up interrupt (I0) wake-up interrupt (I0) wake-up interrupt (I0) Port A Configuration I/O Function Table 8. PORT B Port B Configuration I/O Input Output push-pull/open drain push-pull/open drain Not connected to pad Alternate ICAP1_2: Input Capture #1 Timer 2 EXTCLK_2: External Clock Timer 2 PWMI: PWM input Function Interrupt wake-up interrupt (I0) wake-up interrupt (I0) . PB0 PB1 PB2(1) triggered with pull-up triggered with pull-up Not connected to pad 1. The PB2 bit is not connected to the external. It must be configured as an Input without interrupt, to be used only as an alternate function. 38/126 L9803 Figure 18. Ports PA0-PA7, PB0-PB1I Alternate enable Alternate output 1 0 On-Chip Peripherals M U X VDD P-BUFFER Alternate enable Pull-up condition DR latch Data Bus DDR latch OR latch PAD OR SEL DDR SEL N-BUFFER DR SEL M U X 1 0 Alternate enable GND digital enable Alternate input Interrupt from other bits 39/126 On-Chip Peripherals L9803 5.1.3 Register Description Data registers (PADR) Port A: 0000h Read/Write Reset Value: 0000 0000 (00h) 7 MSB 0 LSB (PBDR) Port B: 0004h Read/Write Reset Value: 0000 0000 (00h) 7 MSB 0 0 0 0 0 LSB Data direction registers (PADDR) Port A: 0001h Read/Write Reset Value: 0000 0000 (00h) (input mode) 7 MSB 0 LSB (PBDDR) Port B: 0005h Read/Write Reset Value: 0000 0000 (00h) (input mode) 7 MSB 0 0 0 0 0 LSB 40/126 L9803 On-Chip Peripherals Option registers (PAOR) Port A: 0002h Read/Write Reset Value: 0000 0000 (00h) (no interrupt) 7 MSB 0 LSB (PBOR) Port B: 0006h Read/Write Reset Value: 0000 0000 (00h) (no interrupt) 7 MSB 0 0 0 0 0 LSB 5.2 5.2.1 16-Bit Timer Introduction The timer consists of a 16-bit free-running counter driven by a programmable prescaler. It may be used for a variety of purposes, including pulse length measurement of up to two input signals (input capture) or generation of up to two output waveforms (output compare and PWM). Pulse lengths and waveform periods can be modulated from a few microseconds to several milliseconds using the timer prescaler and the CPU clock prescaler. 41/126 On-Chip Peripherals L9803 5.2.2 Main Features ● ● ● ● Programmable prescaler: fcpu divided by 2, 4 or 8. Overflow status flag and maskable interrupt External clock input (must be at least 4 times slower than the CPU clock speed) with the choice of active edge Output compare functions with – – – – 2 dedicated 16-bit registers 2 dedicated programmable signals 2 dedicated status flags 1 dedicated maskable interrupt 2 dedicated 16-bit registers 2 dedicated active edge selection signals 2 dedicated status flags 1 dedicated maskable interrupt ● Input capture functions with – – – – ● ● ● Pulse width modulation mode (PWM) One pulse mode 5 alternate functions on I/O ports The Block Diagram is shown in Figure 19 on page 43. Note: Some external pins are not available on all devices. Refer to the device pin out description. 5.2.3 Functional Description Counter The main block of the Programmable Timer is a 16-bit free running upcounter and its associated 16-bit registers. The 16-bit registers are made up of two 8-bit registers called high & low. Counter Register (CR): – – – – Counter High Register (CHR) is the most significant byte (MS Byte). Counter Low Register (CLR) is the least significant byte (LS Byte). Alternate Counter High Register (ACHR) is the most significant byte (MS Byte). Alternate Counter Low Register (ACLR) is the least significant byte (LS Byte). Alternate Counter Register (ACR) These two read-only 16-bit registers contain the same value but with the difference that reading the ACLR register does not clear the TOF bit (Timer overflow flag), located in the Status register (SR). (See note at the end of paragraph titled 16-bit read sequence). Writing in the CLR register or ACLR register resets the free running counter to the FFFCh value. Both counters have a reset value of FFFCh (this is the only value which is reloaded in the 16-bit timer). The reset value of both counters is also FFFCh in One Pulse mode and PWM mode. 42/126 L9803 On-Chip Peripherals The timer clock depends on the clock control bits of the CR2 register, as illustrated in Table 9: Clock Control Bits. The value in the counter register repeats every 131072, 262144 or 524288 CPU clock cycles depending on the CC[1:0] bits. The timer frequency can be fCPU/2, fCPU/4, fCPU/8 or an external frequency. Figure 19. Timer Block Diagram ST7 INTERNAL BUS CPU CLOCK MCU-PERIPHERAL INTERFACE 8 high 8 low high high high high low low low low 2 16 16 8-bit buffer EXEDG 16 1/2 1/4 1/8 16 BIT FREE RUNNING COUNTER COUNTER ALTERNATE REGISTER 8 8 8 8 8 8 8 8 OUTPUT COMPARE REGISTER OUTPUT COMPARE REGISTER INPUT CAPTURE REGISTER INPUT CAPTURE REGISTER 1 2 1 CC1 CC0 16 TIMER INTERNAL BUS 16 16 EXCLK OVERFLOW DETECT CIRCUIT OUTPUT COMPARE CIRCUIT 6 EDGE DETECT CIRCUIT1 EDGE DETECT CIRCUIT2 ICAP1 ICAP2 LATCH1 ICF1 OCF1 TOF ICF2 OCF2 0 0 0 OCMP1 SR ICIE OCIE TOIE FOLV2 FOLV1 OLVL2 IEDG1 OLVL1 OC1E OC2E OPM PWM LATCH2 OCMP2 CC1 CC0 IEDG2 EXEDG CR1 CR2 TIMER INTERRUPT 43/126 On-Chip Peripherals 16-bit read sequence: (from either the Counter Register or the Alternate Counter Register). Beginning of the sequence At t0 Read MSB Other instructions At t0 +∆t Read LSB Sequence completed Returns the buffered L9803 LSB is buffered LSB value at t0 The user must read the MSB first, then the LSB value is buffered automatically. This buffered value remains unchanged until the 16-bit read sequence is completed, even if the user reads the MSB several times. After a complete reading sequence, if only the CLR register or ACLR register are read, they return the LSB of the count value at the time of the read. An overflow occurs when the counter rolls over from FFFFh to 0000h then: ● ● The TOF bit of the SR register is set. A timer interrupt is generated if: – – TOIE bit of the CR1register is set and I bit of the CCR register is cleared. If one of these conditions is false, the interrupt remains pending to be issued as soon as they are both true. Clearing the overflow interrupt request is done by: 1. 2. Note: Reading the SR register while the TOF bit is set. An access (read or write) to the CLR register. The TOF bit is not cleared by accesses to ACLR register. This feature allows simultaneous use of the overflow function and reads of the free running counter at random times (for example, to measure elapsed time) without the risk of clearing the TOF bit erroneously. The timer is not affected by WAIT mode. In HALT mode, the counter stops counting until the mode is exited. Counting then resumes from the previous count (MCU awakened by an interrupt) or from the reset count (MCU awakened by a Reset). External Clock The external clock (where available) is selected if CC0=1 and CC1=1 in CR2 register. The status of the EXEDG bit determines the type of level transition on the external clock pin EXCLK that will trigger the free running counter. The counter is synchronised with the falling edge of the internal CPU clock. At least four falling edges of the CPU clock must occur between two consecutive active edges of the external clock; thus the external clock frequency must be less than a quarter of the CPU clock frequency. 44/126 L9803 Figure 20. Counter Timing Diagram, internal clock divided by 2 CPU CLOCK INTERNAL RESET TIMER CLOCK COUNTER REGISTER OVERFLOW FLAG TOF FFFD FFFE FFFF 0000 0001 On-Chip Peripherals 0002 0003 Figure 21. Counter Timing Diagram, internal clock divided by 4 CPU CLOCK INTERNAL RESET TIMER CLOCK COUNTER REGISTER OVERFLOW FLAG TOF FFFC FFFD 0000 0001 Figure 22. Counter Timing Diagram, internal clock divided by 8 CPU CLOCK INTERNAL RESET TIMER CLOCK COUNTER REGISTER OVERFLOW FLAG TOF FFFC FFFD 0000 Input Capture In this section, the index, i, may be 1 or 2 The two input capture 16-bit registers (ICR1 and ICR2) are used to latch the value of the free running counter after a transition detected by the ICAPi pin (see figure 5) . MS Byte ICRi ICHRi LS Byte ICLRi ICRi register is a read-only register. 45/126 On-Chip Peripherals L9803 The active transition is software programmable through the IEDGi bit of the Control Register (CRi). Timing resolution is one count of the free running counter: (fCPU/(CC1.CC0)). Procedure To use the input capture function select the following in the CR2 register: – – – – – – – Select the timer clock (CC1-CC0) (see Table 9: Clock Control Bits). Select the edge of the active transition on the ICAP2 pin with the IEDG2 bit. Set the ICIE bit to generate an interrupt after an input capture. Select the edge of the active transition on the ICAP1 pin with the IEDG1 bit. ICFi bit is set. The ICRi register contains the value of the free running counter on the active transition on the ICAPi pin (see Figure 23). A timer interrupt is generated if the ICIE bit is set and the I bit is cleared in the CCR register. Otherwise, the interrupt remains pending until both conditions become true. And select the following in the CR1 register: When an input capture occurs: Clearing the Input Capture interrupt request is done by: 1. 2. Note: Reading the SR register while the ICFi bit is set. An access (read or write) to the ICLRi register. After reading the ICHRi register, transfer of input capture data is inhibited until the ICLRi register is also read. The ICRi register always contains the free running counter value which corresponds to the most recent input capture. During HALT mode, if at least one valid input capture edge occurs on the ICAPi pin, the input capture detection circuitry is armed. This does not set any timer flags, and does not “wake-up” the MCU. If the MCU is awoken by an interrupt, the input capture flag will become active, and data corresponding to the first valid edge during HALT mode will be present. 46/126 L9803 Figure 23. Input Capture Block Diagram On-Chip Peripherals ICAP1 EDGE DETECT CIRCUIT2 EDGE DETECT CIRCUIT1 ICIE (Control Register 1) CR1 IEDG1 ICAP2 (Status Register) SR ICR2 ICR1 ICF1 ICF2 0 0 0 16-BIT (Control Register 2) CR2 CC1 CC0 IEDG2 16-BIT FREE RUNNING COUNTER Figure 24. Input Capture Timing Diagram TIMER CLOCK COUNTER REGISTER ICAPi PIN ICAPi FLAG ICAPi REGISTER Note: Active edge is rising edge. FF03 FF01 FF02 FF03 Output Compare In this section, the index, i, may be 1 or 2 because there are 2 output compare functions in the 16-bit timer. This function can be used to control an output waveform or indicate when a period of time has elapsed. When a match is found between the Output Compare register and the free running counter, the output compare function: – – – Assigns pins with a programmable value if the OCiE bit is set Sets a flag in the status register Generates an interrupt if enabled Two 16-bit registers Output Compare Register 1 (OC1R) and Output Compare Register 2 (OC2R) contain the value to be compared to the counter register each timer clock cycle 47/126 On-Chip Peripherals . L9803 MS Byte OCiR OCiHR LS Byte OCiLR These registers are readable and writable and are not affected by the timer hardware. A reset event changes the OCiR value to 8000h. Timing resolution is one count of the free running counter: (fCPU/CC[1:0]). Procedure To use the output compare function, select the following in the CR2 register: – – – – – – – Set the OCiE bit if an output is needed then the OCMPi pin is dedicated to the output compare i function. Select the timer clock (CC[1:0]) (see Table 9: Clock Control Bits). Select the OLVLi bit to applied to the OCMPi pins after the match occurs. Set the OCIE bit to generate an interrupt if it is needed. OCFi bit is set. The OCMPi pin takes OLVLi bit value (OCMPi pin latch is forced low during reset). A timer interrupt is generated if the OCIE bit is set in the CR1 register and the I bit is cleared in the CC register (CC). And select the following in the CR1 register: When a match is found between OCRi register and CR register: The OCRi register value required for a specific timing application can be calculated using the following formula: ∆ t ⋅ f CPU ∆ OC i R = ---------------------PRESC Where: ∆t fCPU PRESC = Output compare period (in seconds) = CPU clock frequency (in Hz) = Timer prescaler factor (2, 4 or 8 depending on CC[1:0] bits, see Table 9: Clock Control Bits) If the timer clock is an external clock, the formula is: ∆OCiR = ∆t · fEXT Where: ∆t fEXT 1. 2. = Output compare period (in seconds) = External timer clock frequency (in hertz) Reading the SR register while the OCFi bit is set. An access (read or write) to the OCiLR register. Clearing the output compare interrupt request (i.e.clearing the OCFi bit) is done by: 48/126 L9803 On-Chip Peripherals The following procedure is recommended to prevent the OCFi bit from being set between the time it is read and the write to the OCiR register: – – – Write to the OCiHR register (further compares are inhibited). Read the SR register (first step of the clearance of the OCFi bit, which may be already set). Write to the OCiLR register (enables the output compare function and clears the OCFi bit). Figure 25. Output Compare Block Diagram 16 BIT FREE RUNNING COUNTER 16-bit OUTPUT COMPARE CIRCUIT 16-bit 16-bit OC1E OC2E CC1 CC0 (Control Register 2) CR2 (Control Register 1) CR1 OCIE FOLV2 FOLV1 OLVL2 OLVL1 Latch 1 OCMP1 Pin OCMP2 Pin OC1R Register OCF1 OCF2 0 0 0 Latch 2 OC2R Register (Status Register) SR Figure 26. Output Compare Timing Diagram, Internal Clock Divided by 2 INTERNAL CPU CLOCK TIMER CLOCK COUNTER OUTPUT COMPARE REGISTER COMPARE REGISTER LATCH OCFi AND OCMPi PIN (OLVLi=1) FFFC FFFD FFFD FFFE FFFF 0000 CPU writes FFFF FFFF Forced Compare Output capability When the FOLVi bit is set by software, the OLVLi bit is copied to the OCMPi pin. The OLVi bit has to be toggled in order to toggle the OCMPi pin when it is enabled (OCiE bit=1). The OCFi bit is then not set by hardware, and thus no interrupt request is generated. FOLVLi bits have no effect in either One-Pulse mode or PWM mode. 49/126 On-Chip Peripherals L9803 One Pulse Mode One Pulse mode enables the generation of a pulse when an external event occurs. This mode is selected via the OPM bit in the CR2 register. The One Pulse mode uses the Input Capture1 function and the Output Compare1 function. Procedure To use One Pulse mode: 1. 2. Load the OC1R register with the value corresponding to the length of the pulse (see the formula in the section). Select the following in the CR1 register: – – – 3. Using the OLVL1 bit, select the level to be applied to the OCMP1 pin after the pulse. Using the OLVL2 bit, select the level to be applied to the OCMP1 pin during the pulse. Select the edge of the active transition on the ICAP1 pin with the IEDG1 bit (the ICAP1 pin must be configured as floating input). Set the OC1E bit, the OCMP1 pin is then dedicated to the Output Compare 1 function. Set the OPM bit. Select the timer clock CC[1:0] (see Table 9: Clock Control Bits). Select the following in the CR2 register: – – – . One pulse mode cycle When event occurs on ICAP1 OCMP1 = OLVL2 Counter is reset to FFFCh ICF1 bit is set When Counter = OCR1 OCMP1 = OLVL1 Then, on a valid event on the ICAP1 pin, the counter is initialized to FFFCh and the OLVL2 bit is loaded on the OCMP1 pin, the ICF1 bit is set and the value FFFDh is loaded in the IC1R register. Because the ICF1 bit is set when an active edge occurs, an interrupt can be generated if the ICIE bit is set. Clearing the Input Capture interrupt request (i.e. clearing the ICFi bit) is done in two steps: 1. 2. Reading the SR register while the ICFi bit is set. An access (read or write) to the ICiLR register. The OC1R register value required for a specific timing application can be calculated using the following formula: t ⋅ f CPU OC i R Value = --------------------- – 5 PRESC Where: 50/126 L9803 t fCPU = Pulse period (in seconds) = CPU clock frequency (in hertz) On-Chip Peripherals PRESC = Timer prescaler factor (2, 4 or 8 depending on the CC[1:0] bits, seeTable 9: Clock Control Bits). If the timer clock is an external clock the formula is: Where: t fEXT = Pulse period (in seconds) = External timer clock frequency (in hertz) When the value of the counter is equal to the value of the contents of the OC1R register, the OLVL1 bit is output on the OCMP1 pin (See Figure 27). Note: 1 2 3 4 The OCF1 bit cannot be set by hardware in One Pulse mode but the OCF2 bit can generate an Output Compare interrupt. When the Pulse Width Modulation (PWM) and One Pulse mode (OPM) bits are both set, the PWM mode is the only active one. If OLVL1=OLVL2 a continuous signal will be seen on the OCMP1 pin. The ICAP1 pin can not be used to perform input capture. The ICAP2 pin can be used to perform input capture (ICF2 can be set and IC2R can be loaded) but the user must take care that the counter is reset each time a valid edge occurs on the ICAP1 pin and ICF1 can also generates interrupt if ICIE is set. When One Pulse mode is used OC1R is dedicated to this mode. Nevertheless OC2R and OCF2 can be used to indicate that a period of time has elapsed but cannot generate an output waveform because the OLVL2 level is dedicated to One Pulse mode. The OCF1 bit cannot be set by hardware in one pulse mode but the OCF2 bit can generate an Output Compare interrupt. The ICF1 bit is set when an active edge occurs and can generate an interrupt if the ICIE bit is set. When the Pulse Width Modulation (PWM) and One Pulse Mode (OPM) bits are both set, the PWM mode is the only active one. Figure 27. One Pulse Mode Timing 5 Note: COUNTER ICAP1 OCMP1 .... FFFC FFFD FFFE 2ED0 2ED1 2ED2 2ED3 FFFC FFFD OLVL2 OLVL1 OLVL2 compare1 Note: IEDG1=1, OCR1=2ED0h, OLVL1=0, OLVL2=1 Pulse Width Modulation Mode Pulse Width Modulation (PWM) mode enables the generation of a signal with a frequency and pulse length determined by the value of the OC1R and OC2R registers. 51/126 On-Chip Peripherals L9803 The Pulse Width Modulation mode uses the complete Output Compare 1 function plus the OC2R register, and so these functions cannot be used when the PWM mode is activated. Procedure To use Pulse Width Modulation mode: 1. 2. 3. Load the OC2R register with the value corresponding to the period of the signal using the formula in the section. Load the OC1R register with the value corresponding to the period of the pulse if OLVL1=0 and OLVL2=1, using the formula in the section. Select the following in the CR1 register: – – 4. Using the OLVL1 bit, select the level to be applied to the OCMP1 pin after a successful comparison with OC1R register. Using the OLVL2 bit, select the level to be applied to the OCMP1 pin after a successful comparison with OC2R register. Set OC1E bit: the OCMP1 pin is then dedicated to the output compare 1 function. Set the PWM bit. Select the timer clock (CC[1:0]) (see Table 9: Clock Control Bits). Select the following in the CR2 register: – – – If OLVL1=1 and OLVL2=0, the length of the positive pulse is the difference between the OC2R and OC1R registers. If OLVL1=OLVL2 a continuous signal will be seen on the OCMP1 pin. Pulse Width Modulation cycle When Counter = OCR1 OCMP1 = OLVL1 When Counter = OCR2 OCMP1 = OLVL2 Counter is reset to FFFCh ICF1 bit is set The OCRi register value required for a specific timing application can be calculated using the following formula: t ⋅ f CPU OC i R Value = --------------------- – 5 PRESC Where: t fCPU = Signal or pulse period (in seconds) = CPU clock frequency (in hertz) PRESC = Timer prescaler factor (2, 4 or 8 depending on CC[1:0] bits, see Table 9: Clock Control Bits If the timer clock is an external clock the formula is: OCiR = t · fEXT -5 Where: 52/126 L9803 t = Signal or pulse period (in seconds) On-Chip Peripherals fEXT = External timer clock frequency (in hertz) The Output Compare 2 event causes the counter to be initialized to FFFCh (See Figure 28 on page 53). Note: 1 2 3 4 After a write instruction to the OCiHR register, the output compare function is inhibited until the OCiLR register is also written. The OCF1 and OCF2 bits cannot be set by hardware in PWM mode, therefore the Output Compare interrupt is inhibited. The ICF1 bit is set by hardware when the counter reaches the OC2R value and can produce a timer interrupt if the ICIE bit is set and the I bit is cleared. In PWM mode the ICAP1 pin can not be used to perform input capture because it is disconnected from the timer. The ICAP2 pin can be used to perform input capture (ICF2 can be set and IC2R can be loaded) but the user must take care that the counter is reset after each period and ICF1 can also generate an interrupt if ICIE is set. When the Pulse Width Modulation (PWM) and One Pulse mode (OPM) bits are both set, the PWM mode is the only active one. Figure 28. Pulse Width Modulation Mode Timing 5 COUNTER OCMP1 34E2 FFFC FFFD FFFE OLVL2 2ED0 2ED1 2ED2 OLVL1 34E2 FFFC OLVL2 compare2 compare1 compare2 Note: OCR1=2ED0h, OCR2=34E2, OLVL1=0, OLVL2= 1 5.2.4 Register Description Each Timer is associated with three control and status registers, and with six pairs of data registers (16-bit values) relating to the two input captures, the two output compares, the counter and the alternate counter. CONTROL REGISTER 1 (CR1) Timer1 Register Address: 0032h Timer2 Register Address: 0042h Read/Write Reset Value: 0000 0000(00h) 7 ICIE OCIE TOIE FOLV2 FOLV1 OLVL2 IEDG1 0 OLVL1 53/126 On-Chip Peripherals Bit 7 = ICIE Input Capture Interrupt Enable. 0: Interrupt is inhibited. L9803 1: A timer interrupt is generated whenever the ICF1 or ICF2 bits of the SR register are set Bit 6 = OCIE Output Compare Interrupt Enable. 0: Interrupt is inhibited. 1: A timer interrupt is generated whenever the OCF1 or OCF2 bits of the SR register are set Bit 5 = TOIE Timer Overflow Interrupt Enable. 0: Interrupt is inhibited. 1: A timer interrupt is enabled whenever the TOF bit of the SR register is set. Bit 4 = FOLV2 Forced Output Compare 2. 0: No effect. 1: Forces the OLVL2 bit to be copied to the OCMP2 pin. Bit 3 = FOLV1 Forced Output Compare 1. 0: No effect. 1: Forces OLVL1 to be copied to the OCMP1 pin. Bit 2 = OLVL2 Output Level 2. This bit is copied to the OCMP2 pin whenever a successful comparison occurs with the OCR2 register. This value is copied to the OCMP1 pin in One Pulse Mode and Pulse Width Modulation mode. Bit 1 = IEDG1 Input Edge 1. This bit determines which type of level transition on the ICAP1 pin will trigger the capture. 0: A falling edge triggers the capture. 1: A rising edge triggers the capture. Bit 0 = OLVL1 Output Level 1. The OLVL1 bit is copied to the OCMP1 pin whenever a successful comparison occurs with the OCR1 register. CONTROL REGISTER 2 (CR2) Timer1 Register Address: 0031h Timer2 Register Address: 0041h 54/126 L9803 Read/Write Reset Value: 0000 0000 (00h) 7 OC1E OC2E OPM PWM CC1 CC0 On-Chip Peripherals 0 IEDG2 EXEDG Bit 7 = OC1E Output Compare 1 Enable. 0: Output Compare 1 function is enabled, but the OCMP1 pin is a general I/O. 1: Output Compare 1 function is enabled, the OCMP1 pin is dedicated to the Output Compare 1 capability of the timer. Bit 6 = OC2E Output Compare 2 Enable. 0: Output Compare 2 function is enabled, but the OCMP2 pin is a general I/O. 1: Output Compare 2 function is enabled, the OCMP2 pin is dedicated to the Output Compare 2 capability of the timer. Bit 5 = OPM One Pulse Mode. 0: One Pulse Mode is not active. 1: One Pulse Mode is active, the ICAP1 pin can be used to trigger one pulse on the OCMP1 pin; the active transition is given by the IEDG1 bit. The length of the generated pulse depends on the contents of the OCR1 register. Bit 4 = PWM Pulse Width Modulation. 0: PWM mode is not active. 1: PWM mode is active, the OCMP1 pin outputs a programmable cyclic signal; the length of the pulse depends on the value of OCR1 register; the period depends on the value of OCR2 register. Bit 3, 2 = CC1-CC0 Clock Control. The value of the timer clock depends on these bits: Table 9. Clock Control Bits CC1 0 0 1 1 CC0 0 1 0 1 Timer Clock fCPU / 4 fCPU / 2 fCPU / 8 External Clock where available 55/126 On-Chip Peripherals L9803 Bit 1 = IEDG2 Input Edge 2. This bit determines which type of level transition on the ICAP2 pin will trigger the capture 0: A falling edge triggers the capture. 1: A rising edge triggers the capture. Bit 0 = EXEDG External Clock Edge. This bit determines which type of level transition on the external clock pin EXCLK will trigger the free running counter. 0: A falling edge triggers the free running counter. 1: A rising edge triggers the free running counter. STATUS REGISTER (SR) Timer1 Register Address: 0033h Timer2 Register Address: 0043h Read Only Reset Value: 0000 0000 (00h) The three least significant bits are not used. 7 ICF1 OCF1 TOF ICF2 OCF2 0 Bit 7 = ICF1 Input Capture Flag 1. 0: 1: No input capture (reset value) An input capture has occurred. To clear this bit, first read the SR register, then read or write the low byte of the ICR1 (ICLR1) register. Bit 6 = OCF1 Output Compare Flag 1. 0: 1: No match (reset value) The content of the free running counter has matched the content of the OCR1 register. To clear this bit, first read the SR register, then read or write the low byte of the OCR1 (OCLR1) register. Bit 5 = TOF Timer Overflow. 0: 1: Note: No timer overflow (reset value) The free running counter rolled over from FFFFh to 0000h. To clear this bit, first read the SR register, then read or write the low byte of the CR (CLR) register. Reading or writing the ACLR register do not clear TOF. Bit 4 = ICF2 Input Capture Flag 2. 0: No input capture (reset value) 56/126 L9803 1: On-Chip Peripherals An input capture has occurred.To clear this bit, first read the SR register, then read or write the low byte of the ICR2 (ICLR2) register. Bit 3 = OCF2 Output Compare Flag 2. 0: 1: No match (reset value) The content of the free running counter has matched the content of the OCR2 register. To clear this bit, first read the SR register, then read or write the low byte of the OCR2 (OCLR2) register. Bit 2-0 = Unused. INPUT CAPTURE 1 HIGH REGISTER (ICHR1) Timer1 Register Address: 0034h Timer2 Register Address: 0044h Read Only Reset Value: Undefined This is an 8-bit read only register that contains the high part of the counter value (transferred by the input capture 1 event). 7 MSB 0 LSB INPUT CAPTURE 1 LOW REGISTER (ICLR1) Timer1 Register Address: 0035h Timer2 Register Address: 0045h Read Only Reset Value: Undefined This is an 8-bit read only register that contains the low part of the counter value (transferred by the input capture 1 event). 7 MSB 0 LSB 57/126 On-Chip Peripherals OUTPUT COMPARE 1 HIGH REGISTER (OCHR1) Timer1 Register Address: 0036h Timer2 Register Address: 0046h Read/Write Reset Value: 1000 0000 (80h) L9803 This is an 8-bit register that contains the high part of the value to be compared to the CHR register. 7 MSB 0 LSB OUTPUT COMPARE 1 LOW REGISTER (OCLR1) Timer1 Register Address: 0037h Timer2 Register Address: 0047h Read/Write Reset Value: 0000 0000 (00h) This is an 8-bit register that contains the low part of the value to be compared to the CLR register. 7 MSB 0 LSB OUTPUT COMPARE 2 HIGH REGISTER (OCHR2) Timer1 Register Address: 003Eh Timer2 Register Address: 004Eh Read/Write Reset Value: 1000 0000 (80h) This is an 8-bit register that contains the high part of the value to be compared to the CHR register. . 7 MSB 0 LSB OUTPUT COMPARE 2 LOW REGISTER (OCLR2) Timer1 Register Address: 003Fh Timer2 Register Address: 004Fh Read/Write Reset Value: 0000 0000 (00h) This is an 8-bit register that contains the low part of the value to be compared to the CLR register. . 7 MSB 0 LSB 58/126 L9803 COUNTER HIGH REGISTER (CHR) Timer1 Register Address: 0038h Timer2 Register Address: 0048h Read Only Reset Value: 1111 1111 (FFh) On-Chip Peripherals This is an 8-bit register that contains the high part of the counter value. 7 MSB 0 LSB COUNTER LOW REGISTER (CLR) Timer1 Register Address: 0039h Timer2 Register Address: 0049h Read/Write Reset Value: 1111 1100 (FCh) This is an 8-bit register that contains the low part of the counter value. A write to this register resets the counter. An access to this register after accessing the SR register clears the TOF bit.16-BIT. 7 MSB 0 LSB ALTERNATE COUNTER HIGH REGISTER (ACHR) Timer1 Register Address: 003Ah Timer2 Register Address: 004Ah Read Only Reset Value: 1111 1111 (FFh) This is an 8-bit register that contains the high part of the counter value. . 7 MSB 0 LSB ALTERNATE COUNTER LOW REGISTER (ACLR) Timer1 Register Address: 003Bh Timer2 Register Address: 004Bh Read/Write Reset Value: 1111 1100 (FCh) This is an 8-bit register that contains the low part of the counter value. A write to this register resets the counter. An access to this register after an access to SR register does not clear the TOF bit in SR register. 59/126 On-Chip Peripherals L9803 7 MSB 0 LSB INPUT CAPTURE 2 HIGH REGISTER (ICHR2) Timer1 Register Address: 003Ch Timer2 Register Address: 004Ch Read Only Reset Value: Undefined This is an 8-bit read only register that contains the high part of the counter value (transferred by the Input Capture 2 event). 7 MSB 0 LSB INPUT CAPTURE 2 LOW REGISTER (ICLR2) Timer1 Register Address: 003Dh Timer2 Register Address: 004Dh Read Only Reset Value: Undefined This is an 8-bit read only register that contains the low part of the counter value (transferred by the Input Capture 2 event). 7 MSB 0 LSB Table 10. Address (Hex.) 16-Bit Timer Register Map and Reset Values Register Name 7 ICIE 0 OC1E 0 ICF1 0 MSB MSB MSB MSB 6 OCIE 0 OC2E 0 OCF1 0 5 TOIE 0 OPM 0 TOF 0 4 FOLV2 0 PWM 0 ICF2 0 3 FOLV1 0 CC1 0 OCF2 0 2 OLVL2 0 CC0 0 0 1 IEDG1 0 IEDG2 0 0 0 OLVL1 0 EXEDG 0 0 LSB LSB LSB LSB - Timer1: 32 CR1 Timer2: 42 Reset Value Timer1: 31 CR2 Timer2: 41 Reset Value Timer1: 33 SR Timer2: 43 Reset Value Timer1: 34 ICHR1 Timer2: 44 Reset Value Timer1: 35 ICLR1 Timer2: 45 Reset Value Timer1: 36 OCHR1 Timer2: 46 Reset Value Timer1: 37 OCLR1 Timer2: 47 Reset Value 60/126 L9803 Table 10. Address (Hex.) On-Chip Peripherals 16-Bit Timer Register Map and Reset Values (continued) Register Name 7 MSB MSB MSB 1 MSB 1 MSB 1 MSB 1 MSB MSB 6 5 4 3 2 1 0 LSB LSB LSB 1 LSB 0 LSB 1 LSB 0 LSB LSB - Timer1: 3E OCHR2 Timer2: 4E Reset Value Timer1: 3F OCLR2 Timer2: 4F Reset Value Timer1: 38 CHR Timer2: 48 Reset Value Timer1: 39 CLR Timer2: 49 Reset Value Timer1: 3A ACHR Timer2: 4A Reset Value Timer1: 3B ACLR Timer2: 4B Reset Value Timer1: 3C ICHR2 Timer2: 4C Reset Value Timer1: 3D ICLR2 Timer2: 4D Reset Value - - - - - - 1 1 1 1 - 1 1 1 1 - 1 1 1 1 - 1 1 1 1 - 1 1 1 1 - 1 0 1 0 - 5.3 5.3.1 PWM Generator Introduction This PWM peripheral includes a 16-bit Pulse Width Modulator (PWM) and a programmable prescaler able to generate an internal clock with period as long as 128*TCPU. The repetition rate of the 16-Bit PWM output can be defined by a dedicated register (fCPU/CYREG); its resolution is defined by the internal clock as per the prescaler programming. Main Features – – – – Programmable prescaler: fCPU divided by 2, 4, 8, 16, 32, 64 or 128. 1 control register 2 dedicated 16-bit registers for cycle and duty control 1 dedicated maskable interrupt Procedure To use the pulse width modulation peripheral, the EN_PWM bit in CONREG register must be set. Load PS(2:0) in CONREG register to define the programmable prescaler. Load the CYREG register with the value defining the cycle length (in internal clock periods). The 16 bits of this register are separated in two registers: CYREGH and CYREGL. 61/126 On-Chip Peripherals L9803 Load the DUTYREG register with the value corresponding to the pulse length (in internal cycle periods). The 16 bits of this register are separated in two registers: DUTYREGH and DUTYREGL. The counter is reset to zero when EN_PWM bit is reset. Writing the DUTYREG and CYREG registers has no effect on the current PWM cycle. The cycle or duty cycle change take place only after the first overflow of the counter. The suggested procedures to change the PWM parameters are the following: Duty Cycle control: – Write the low and high DUTYREG registers. A writing only on one DUTYREG register has no effect until both registers are written. The current PWM cycle will be completed. The new duty cycle will be effective at the following PWM cycle, with respect to the last DUTYREG writing. Cycle control: – Write the low and high CYREG register A writing only on one CYREG register has no effect until both registers are written. The current PWM cycle will be completed. The new cycle will be effective at the following PWM cycle, with respect to the last CYREG writing. Another possible procedure is: – – – Reset the EN_PWM bit. Write the wanted configuration in CYREG and DUTYREG.. Set the EN_PWM bit. If the EN_PWM bit is set after being reset, the current values of DUTYREG and CYREG are determining the output waveform, no matter if only the low or the high part, or both were written. The first time EN_PWM is set, if CYREG and DUTYREG were not previously written, the output is permanently low, because the default value of the registers is 00h. Changing the Prescaler ratio writing PS(2:0) in CONREG has immediate effect on the waveform frequency. 5.3.2 Functional Description The PWM module consists of a 16-bit counter, a comparator and the cycle generation logic. PWM Generation The counter increments continuously, clocked at internal clock generated by prescaler. Whenever the 16 bits of the counter (defined as the PWM counter) overflow, the output level is set. The overflow value is defined by CYREG register. The state of the PWM counter is continuously compared to the PWM binary weight, as defined in DUTYREG register, and when a match occurs the output level is reset. 62/126 L9803 Figure 29. PWM Cycle Pulse Width Modulation cycle When Counter = DUTYREG On-Chip Peripherals OUT PWM = 0 When Counter = CYREG OUT PWM = 1 Counter is reset Note: If the CYREG value is minor or equal than DUTYREG value, PWM output remains set. With a DUTYREG value of 0000h, the PWM output is permanently at low level, no matter of the value of CYREG. With a DUTYREG value of FFFFh, the PWM output is permanently at high level. Interrupt Request The EN_INT bit in CONREG register must be set to enable the interrupt generation. When the 16 bits of the counter roll-over CYCLEREG value, interrupt request is set. The interrupt request is cleared when any of the PWM registers is written. Figure 30. PWM Generation COUNTER Interrupt Generation CYREG value COMPARE VALUE 000 t PWM OUTPUT t T(INTERNAL CLOCK) x Cyreg_value 5.3.3 Register Description The PWM is associated with a 8-bit control registers, and with two 16-bit data registers, each split in two 8-bit registers. PWM CYCLE REGISTER LOW (CYREGL) PWM1 Register Address: 0011h PWM2 Register Address: 0019h Read/Write Reset Value: 0000 0000 (00h) 63/126 On-Chip Peripherals L9803 This is an 8-bit register that contains the low part of the value to be multiplied by internal clock period. 7 MSB 0 LSB PWM CYCLE REGISTER HIGH (CYREGH) PWM1 Register Address: 0010h PWM2 Register Address: 0018h Read/Write Reset Value: 0000 0000 (00h) This is an 8-bit register that contains the high part of the value to be multiplied by internal clock period. . 7 MSB 0 LSB PWM DUTYCYCLE REGISTER LOW (DUTYREGL) PWM1 Register Address: 0013h PWM2 Register Address: 001Bh Read/Write Reset Value: 0000 0000 (00h) This is an 8-bit register that contains the low part of the value corresponding to the binary weight of the PWM pulse. 7 MSB 0 LSB PWM DUTYCYCLE REGISTER HIGH (DUTYREGH) PWM1 Register Address: 0012h PWM2 Register Address: 001Ah Read/Write Reset Value: 0000 0000 (00h) This is an 8-bit register that contains the high part of the value corresponding to the binary weight of the PWM pulse. 7 MSB 0 LSB PWM CONTROL REGISTER (CONREG) PWM1 Register Address: 0014h PWM2 Register Address: 001Ch 64/126 L9803 Read/Write Reset Value: 0000 0000 (00h) 7 0 0 0 4 PS2 3 PS1 2 PS0 On-Chip Peripherals 1 EN_ INT 0 EN_ PWM Bit 0= EN _PWM: 1 = enables the PWM output, 0 = disables PWM output. Bit 1= EN _INT: 1 = enables interrupt request, 0 disables interrupt request. Bit 4, 3, 2= PS2,PS1,PS0: prescaler bits The value of the PWM internal clock depends on these bits. PWM internal clock fCPU fCPU / 2 fCPU / 4 fCPU / 8 fCPU / 16 fCPU / 32 fCPU / 64 fCPU / 128 PS2 0 0 0 0 1 1 1 1 PS1 0 0 1 1 0 0 1 1 PS0 0 1 0 1 0 1 0 1 Bit 5, 6, 7= not used. PWM COUNTER REGISTER LOW (CTL) PWM1 Register Address: 0016h PWM2 Register Address: 001Eh Read Only Reset Value: 0000 0000 (00h) This is an 8-bit register that contains the low part of the PWM counter value. 7 MSB 0 LSB PWM COUNTER REGISTER HIGH(CTH) PWM1 Register Address: 0015h PWM2 Register Address: 001Dh Read Only Reset Value: 0000 0000 (00h) This is an 8-bit register that contains the high part of the PWM counter value. 65/126 On-Chip Peripherals L9803 7 MSB 0 LSB Table 11. PWM Timing (fCPU = 8MHz) Tinternal clock 1/f in * 2 ps 1/f in * 2 1/f in * 2 ps ps Prescaler (PS) 0 1 2 3 4 5 6 7 CYREG @16 bit Resolution 1/f in * 2 ps * 1.....1/f in * 2 ps * 65535 1/f in * 2 1/f in * 2 ps ps PWM cycle @ fin=8MHz 0.125 µs..... ~8192 µs 0.25 µs....... ~16384 µs 0.5 µs......... ~32768 µs 1 µs............ 65535 µs 2 µs............ 131070 µs 4 µs............ 262140 µs 8 µs............ 524280 µs 16 µs.......... 1048560 µs * 1.....1/f in * 2 * 1.....1/f in * 2 ps ps * 65535 * 65535 1/f in * 2 ps 1/f in * 2 1/f in * 2 1/f in * 2 ps ps ps 1/f in * 2 ps * 1.....1/f in * 2 ps * 65535 1/f in * 2 1/f in * 2 1/f in * 2 ps ps ps * 1.....1/f in * 2 * 1.....1/f in * 2 * 1.....1/f in * 2 ps ps ps * 65535 * 65535 * 65535 1/f in * 2 ps 1/f in * 2 ps * 1.....1/f in * 2 ps * 65535 Figure 31. PWM Block Diagram data bus conreg | . | . | . | ps1 | ps2 | ps3 | en_int | en_pwm | dutyreg 2 16 cyreg 16 3 COMPARATOR1 COMPARATOR2 7 6 5 4 3 2 1 M U X 16-bit counter PWM logic clock IRQ 66/126 L9803 On-Chip Peripherals 5.4 5.4.1 PWM I/O Introduction The PWM I/O interface is a circuit able to connect internal logic circuits with external high voltage lines. The two interfaces represent respectively the receiver and the transmitter section of a standard IS0 9141 transceiver. Connecting PWMO and PWMI together a standard K bus (ISO 9141) can be realized. Voltage thresholds are referred to the battery voltage connected to VBR pin. This pin must be used as reference for the K bus. Voltage drops between this pin and the battery line can cause thresholds mismatch between the L9803 ISO trasceiver and the counterpart trasceiver(s) connected to the same bus line. See Figure 32 for a block diagram description of the two interfaces. Figure 32. PWM I/O Block Diagram Battery VBR VDD PWMI + TIMER CAPTURE INPUT PB2 REGISTER BIT K bus PWMO VDD PWM2 OUTPUT 5.4.2 PWMO PWMO is an output line, directly driven by the PWM2 output signal. The circuit translates the logic levels of PWM2 output to voltage levels referred to the VB supply (see Figure 32). When PWM2=0 the open drain is switched off, in the other case the PWMO line is pulled down by the open drain driver. PWMO is protected against short circuit to battery by a dedicated circuit that limits the current sunk by the output transistor. When the limiter is activated the voltage on PWMO pin rises up. If the limiter remains active for more than 25µs the driver is switched off. If the battery or ground connection are lost, the PWMO line shows a controlled impedance characteristic (see Figure 33). PWM0 is high at NRESET is asserted. 67/126 On-Chip Peripherals Figure 33. Impedance at PWMO/I pin IK L9803 50KΩ 5 µA 14V VK 50KΩ 5.4.3 PWMI PWMI is an input line, directly connected to PB2 bit. The circuit translates the voltage levels referred to VB voltage supply to the internal logic levels (see Figure 32). When the voltage on PWMI pin is higher than VB/2 PB2 reads an high logic level. If the bit PWMI in DCSR register is set (see Section 3.2.1), PWMI is directly connected with the Input Capture 2 on Timer 2, which is otherwise connected in alternate function to PA7 (see Figure 34). An internal pull down current generator (5µA) allows to detect the Open Bus condition (external pull up missing). If the battery or ground connection are lost, the PWMI line shows a controlled impedance characteristic (see Figure 34). Figure 34. PWMI function PORT .............. ..... PA7 PA(7) PA(7) ALTERNATE INPUT 0 M U X PWM INPUT 1 TIMER 2 PB(2) PWM I/O ICAP2 PWMI PIEN DCSR Describe the register DCSR (0022h) as reported in Table 1. 68/126 L9803 On-Chip Peripherals 5.5 5.5.1 10-BIT A/D Converter (AD10) Introduction The Analog to Digital converter is a single 10-bit successive approximation converter with 4 input channels. Analog voltage from external sources are input to the converter through AD2,AD3 and AD4 pins. Channel 1 (AD1) is connected to the internal temperature sensor (see Section 5.5.5). Note: The anti aliasing filtering must be accomplished using an external RC filter. The internal AD1 channel is filtered by an RC network with approx. 1µs time constant. 5.5.2 Functional Description The result of the conversion is stored in 2 registers: the Data Register High (ADCDRH) and the Data Register Low (ADCDRL). The A/D converter is enabled by setting the ADST bit in ADCCSR Register. Bits CH1 and CH0 of ADCCSR Register select the channel to be converted. The high and low reference voltage are connected to pins VCC and AGND. When enabled, the A/D converter performs a complete conversion in 14µs (with system clock fCPU=8Mhz). The total conversion time includes multiplex, sampling of the input voltage, 10-bit conversion and writing DRH and DRL registers. When the conversion is completed COCO bit (COnversion COmpleted) is set in ADCCSR. A conversion starts from the moment ADST bit is set. When a conversion is running it is possible to write the ADCCSR without stopping the ADC operations, because all the data in ADCCSR are latched when ADST is set. This property allows to select a different channel to be processed during the next conversion or to manage the interrupt enable bit. The new setting will have effect on the next conversion (including interrupt generation) At the end of the conversion ADST is reset and COCO bit is set. Note: To start a new conversion the ADST must be set after the completion of the current one. Any writing to ADST when a conversion is running (COCO=0) has no effect since ADST bit is automatically reset by the end of conversion event. 69/126 On-Chip Peripherals Figure 35. Block diagram of the Analog to Digital Converter L9803 clk 8Mhz CSR d i v inputs M U X Vin 2 Mhz ADST logic VCC ADIE CH1 CH0 latch start conversion end conversion DRH DRL sampling + conversion AGND ..... AD0 AD9 WR 5.5.3 Input Selections and Sampling The input section of the ADC includes the analog multiplexer and a buffer. The input of the buffer is permanently connected to the multiplexer output. The buffer output is fed to the sample and hold circuit. The multiplexer is driven with CH1 and CH0 bit only after ADST is set. Starting from this event, the sampler follows the selected input signal for 2.5us and then holds it for the remaining conversion time (i.e. when the conversion is actually running). 5.5.4 Interrupt Management If ADIE bit is set in register ADCCSR, an interrupt is generated when a conversion is completed (i.e. when COCO is set). The interrupt request is cleared when any of the ADC registers is access (either read or write). Enabling/disabling the interrupt generation while the conversion is running has no effect on the current conversion. ADIE value is latched when ADST is set and this internal value holds all the conversion time long. 5.5.5 Temperature Sensing The AD1 input is internally connected to the output of a temperature sensing circuit. 70/126 L9803 On-Chip Peripherals The sensor generates a voltage proportional to the absolute temperature of the die. It works over the whole temperature range, with a minimum resolution of 1LSB/°K (5mV/°K) (Figure 36 shows the indicative voltage output of the sensor). Note The voltage output of the sensor is only related to the absolute temperature of the silicon junctions. Junction temperature and ambient temperature must be related taking in account the power dissipated by the device and the thermal resistance Rthje between the silicon and the environment around the application board. Figure 36. Temperature Sensor output VTEMP 2.5 max 2.2 1.9 1.6 1.3 1.0 223 273 323 373 min Temperature (°K) 423 473 The output of the sensor is not ratiometric with the voltage reference for the ADC conversion (VCC). When calculating the ADC reading error of this signal the variation of VCC must be accounted. Additional errors are due to the intrinsic spread of the sensor characteristic. 5.5.6 Precise Temperature Measurement To allow a more precise measurement of the temperature a trimming procedure can be adopted (on request). The temperature is measured in EWS and two values are stored in four EEPROM bytes (see memory map): T0L,T0H: temperature of the trimming measurement (in Kelvin). VT0L,VT0H: output value of the ADC corresponding to T0 (in number of LSBs). The corrected measurement of the temperature in Kelvin must be accomplished in the following way: TEMP (in °K) = VTEMP * T0 / VT0 where VTEMP is the output code in LSB of the ADC corresponding to the measurement. Example: If the value stored in EEPROM are: 0C7Ch: 01h ->T0H 0C7Dh: 43h ->T0L 0C7Eh: 01h -> VT0H 0C7Fh: 5Ch -> VT0L 71/126 On-Chip Peripherals T0 = 0143h = 323K (50 Celsius) VTo = 015Ch = 348 LSB (conversion of 1.7V, sensor output) L9803 and the sensor output is 2V, converted by the ADC in code 0110011001 = 019Ah = 410LSB, the temperature of the chip is TEMP = 019Ah * 0143h / 015Ch = 017Ch equivalent to: TEMP = 410 * 323 / 348 = 380 K = 107 °C Note: The sensor circuit may have two kind of error: one translating its output characteristic up and down and the other changing its slope. The described trimming recovers only the translation errors but can not recover slope error. After trimming, being TTRIM the trimming temperature, the specified precision can be achieved in the range TTRIM-80, max[TTRIM+80, 150°C]. Precision is related to the read temperature in Kelvin. 5.5.7 Register Description CONTROL/STATUS REGISTER (ADCCSR) Address: 0072h — Read/Write Reset Value: 0010 0000 (20h) 7 0 0 COCO ADIE 0 ADST CH1 0 CH0 Bit 7,6 = Reserved Bit 5 =COCO (Read Only) Conversion Complete COCO is set (by the ADC) as soon as a conversion is completed (results can be read). COCO is cleared by setting ADST=1 (start of new conversion). If COCO=0 a conversion is running, if COCO=1 no conversion is running. Bit 4 = ADIE A/D Interrupt Enable This bit is used to enable / disable the interrupt function: 0: interrupt disabled 1: interrupt enabled Bit 3= Reserved Bit 2= ADST Start Conversion When this bit is set a new conversion starts. ADST is automatically reset when the conversion is completed (COCO=1). Bits 1-0 = CH1-CH0 Channel Selection These bits select the analog input to convert. See Table 12 for reference. 72/126 L9803 Table 12. CH1 0 0 1 1 On-Chip Peripherals ADC Channel Selection Table CH0 0 1 0 1 Channel AD1, Temperature Sensor AD2, external input AD3, external input AD4, external input DATA REGISTER HIGH (ADCDRH) Address: 0070h — Read Only Reset Value: 00000 0000 (00h) 7 0 0 0 0 0 0 AD9 0 AD8 Bit 1:0 = AD9-AD8 Analog Converted Value This register contains the high part of the converted analog value DATA REGISTER LOW (ADCDRL) Address: 0071h — Read Only Reset Value: 00000 0000 (00h) 7 AD7 AD6 AD5 AD4 AD3 AD2 AD1 0 AD0 Bit 7:0 = AD7-AD0 Analog Converted Value This register contains the low part of the converted analog value 73/126 On-Chip Peripherals L9803 5.6 5.6.1 Controller Area Network (CAN) Introduction This peripheral is designed to support serial data exchanges using a multi-master contention based priority scheme as described in CAN specification Rev. 2.0 part A. It can also be connected to a 2.0 B network without problems, since extended frames are checked for correctness and acknowledged accordingly although such frames cannot be transmitted nor received. The same applies to overload frames which are recognized but never initiated. Figure 37. CAN Block Diagram ST7 Internal Bus ST7 Interface TX/RX Buffer 1 10 Bytes TX/RX Buffer 2 10 Bytes TX/RX Buffer 3 10 Bytes ID Filter 0 4 Bytes ID Filter 1 4 Bytes PSR BRPR BTR RX BTL BCDL SHREG ICR ISR TX EML CRC CSR CAN 2.0B passive Core TECR RECR 74/126 L9803 On-Chip Peripherals 5.6.2 Main Features ● ● ● ● ● ● ● ● ● ● ● ● ● ● Support of CAN specification 2.0A and 2.0B passive Three prioritized 10-byte Transmit/Receive message buffers Two programmable global 12-bit message acceptance filters Programmable baud rates up to 1 MBit/s Buffer flip-flopping capability in transmission Maskable interrupts for transmit, receive (one per buffer), error and wake-up Automatic low-power mode after 20 recessive bits or on demand (standby mode) Interrupt-driven wake-up from standby mode upon reception of dominant pulse Optional dominant pulse transmission on leaving standby mode Automatic message queuing for transmission upon writing of data byte 7 Programmable loop-back mode for self-test operation Advanced error detection and diagnosis functions Software-efficient buffer mapping at a unique address space Scalable architecture. 5.6.3 Functional Description Frame Formats A summary of all the CAN frame formats is given in Figure 38 for reference. It covers only the standard frame format since the extended one is only acknowledged. A message begins with a start bit called Start Of Frame (SOF). This bit is followed by the arbitration field which contains the 11-bit identifier (ID) and the Remote Transmission Request bit (RTR). The RTR bit indicates whether it is a data frame or a remote request frame. A remote request frame does not have any data byte. The control field contains the Identifier Extension bit (IDE), which indicates standard or extended format, a reserved bit (ro) and, in the last four bits, a count of the data bytes (DLC). The data field ranges from zero to eight bytes and is followed by the Cyclic Redundancy Check (CRC) used as a frame integrity check for detecting bit errors. The acknowledgement (ACK) field comprises the ACK slot and the ACK delimiter. The bit in the ACK slot is placed on the bus by the transmitter as a recessive bit (logical 1). It is overwritten as a dominant bit (logical 0) by those receivers which have at this time received the data correctly. In this way, the transmitting node can be assured that at least one receiver has correctly received its message. Note that messages are acknowledged by the receivers regardless of the outcome of the acceptance test. The end of the message is indicated by the End Of Frame (EOF). The intermission field defines the minimum number of bit periods separating consecutive messages. If there is no subsequent bus access by any station, the bus remains idle. 75/126 On-Chip Peripherals L9803 Hardware Blocks The CAN controller contains the following functional blocks (refer to Figure 37): ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ST7 Interface: buffering of the ST7 internal bus and address decoding of the CAN registers. TX/RX Buffers: three 10-byte buffers for transmission and reception of maximum length messages. ID Filters: two 12-bit compare and don’t care masks for message acceptance filtering. PSR: page selection register (see memory map). BRPR: clock divider for different data rates. BTR: bit timing register. ICR: interrupt control register. ISR: interrupt status register. CSR: general purpose control/status register. TECR: transmit error counter register. RECR: receive error counter register. BTL: bit timing logic providing programmable bit sampling and bit clock generation for synchronization of the controller. BCDL: bit coding logic generating a NRZ-coded datastream with stuff bits. SHREG: 8-bit shift register for serialization of data to be transmitted and parallelisation of received data. CRC: 15-bit CRC calculator and checker. EML: error detection and management logic. CAN Core: CAN 2.0B passive protocol controller. 76/126 L9803 Figure 38. CAN Frames On-Chip Peripherals Inter-Frame Space Data Frame 44 + 8 * N Inter-Frame Space or Overload Frame Arbitration Field Control Field Data Field 12 ID SOF RTR IDE r0 6 DLC 8*N CRC Field 16 CRC Ack Field 2 7 EOF Inter-Frame Space Remote Frame 44 Arbitration Field Control Field 12 ID RTR IDE r0 SOF 6 DLC CRC Field 16 CRC Ack Field 2 End Of Frame 7 Data Frame or Remote Frame Error Frame Inter-Frame Space or Overload Frame Error Flag Flag Echo Error Delimiter 6 ≤6 8 Any Frame Inter-Frame Space Bus Idle Data Frame or Remote Frame Notes: •0 255 the BOFF bit gets set and the EPSV bit gets cleared BUS OFF Bit Timing Logic The bit timing logic monitors the serial bus-line and performs sampling and adjustment of the sample point by synchronizing on the start-bit edge and resynchronizing on following edges. Its operation may be explained simply when the nominal bit time is divided into three segments as follows: ● ● Synchronisation segment (SYNC_SEG): a bit change is expected to lie within this time segment. It has a fixed length of one time quanta (1 x tCAN). Bit segment 1 (BS1): defines the location of the sample point. It includes the PROP_SEG and PHASE_SEG1 of the CAN standard. Its duration is programmable between 1 and 16 time quanta but may be automatically lengthened to compensate for positive phase drifts due to differences in the frequency of the various nodes of the network. Bit segment 2 (BS2): defines the location of the transmit point. It represents the PHASE_SEG2 of the CAN standard. Its duration is programmable between 1 and 8 time quanta but may also be automatically shortened to compensate for negative phase drifts. Resynchronization Jump Width (RJW): defines an upper bound to the amount of lengthening or shortening of the bit segments. It is programmable between 1 and 4 time quanta. ● ● To guarantee the correct behaviour of the CAN controller, SYNC_SEG + BS1 + BS2 must be greater than or equal to 5 time quanta. For a detailed description of the CAN resynchronization mechanism and other bit timing configuration constraints, please refer to the CAN Specification - Bosh - Version 2. 80/126 L9803 On-Chip Peripherals As a safeguard against programming errors, the configuration of the Bit Timing Register (BTR) is only possible while the device is in STANDBY mode. Figure 41. Bit Timing NOMINAL BIT TIME SYNC_SEG BIT SEGMENT 1 (BS1) BIT SEGMENT 2 (BS2) 1 x tCAN tBS1 tBS2 SAMPLE POINT TRANSMIT POINT 5.6.4 Register Description The CAN registers are organized as 6 general purpose registers plus 5 pages of 16 registers spanning the same address space and primarily used for message and filter storage. The page actually selected is defined by the content of the Page Selection Register. Refer to Figure 42. General Purpose Registers INTERRUPT STATUS REGISTER (ISR) Read/Write Reset Value: 00h 7 RXIF3 RXIF2 RXIF1 TXIF SCIF ORIF TEIF 0 EPND Bit 7 = RXIF3 Receive Interrupt Flag for Buffer 3 − Read/Clear Set by hardware to signal that a new error-free message is available in buffer 3. Cleared by software to release buffer 3. Also cleared by resetting bit RDY of BCSR3. − Read/Clear Bit 6 = RXIF2 Receive Interrupt Flag for Buffer 2 Set by hardware to signal that a new error-free message is available in buffer 2. Cleared by software to release buffer 2. Also cleared by resetting bit RDY of BCSR2. − Read/Clear Bit 5 = RXIF1 Receive Interrupt Flag for Buffer 1 Set by hardware to signal that a new error-free message is available in buffer 1. Cleared by software to release buffer 1. Also cleared by resetting bit RDY of BCSR1. − Read/Clear Bit 4 = TXIF Transmit Interrupt Flag Set by hardware to signal that the highest priority message queued for transmission has been successfully transmitted (ETX = 0) or that it has passed successfully the arbitration 81/126 On-Chip Peripherals (ETX = 1). Cleared by software. L9803 Bit 3 = SCIF Status Change Interrupt Flag − Read/Clear Set by hardware to signal the reception of a dominant bit while in standby or a change from error active to error passive and bus-off while in run. Also signals any receive error when ESCI = 1. Cleared by software. Bit 2 = ORIF Overrun Interrupt Flag − Read/Clear Set by hardware to signal that a message could not be stored because no receive buffer was available. Cleared by software. − Read/Clear Bit 1 = TEIF Transmit Error Interrupt Flag Set by hardware to signal that an error occurred during the transmission of the highest priority message queued for transmission. Cleared by software. Bit 0 = EPND Error Interrupt Pending − Read Only Set by hardware when at least one of the three error interrupt flags SCIF, ORIF or TEIF is set. Reset by hardware when all error interrupt flags have been cleared. Caution: Interrupt flags are reset by writing a "0" to the corresponding bit position. The appropriate way consists in writing an immediate mask or the one’s complement of the register content initially read by the interrupt handler. Bit manipulation instruction BRES should never be used due to its read-modify-write nature. INTERRUPT CONTROL REGISTER (ICR) Read/Write Reset Value: 00h 7 0 ESCI RXIE TXIE SCIE ORIE TEIE 0 ETX − Read/Set/Clear Bit 6 = ESCI Extended Status Change Interrupt Set by software to specify that SCIF is to be set on receive errors also. Cleared by software to set SCIF only on status changes and wake-up but not on all receive errors. − Read/Set/Clear Bit 5 = RXIE Receive Interrupt Enable Set by software to enable an interrupt request whenever a message has been received free of errors. Cleared by software to disable receive interrupt requests. 82/126 L9803 On-Chip Peripherals Bit 4 = TXIE Transmit Interrupt Enable − Read/Set/Clear Set by software to enable an interrupt request whenever a message has been successfully transmitted. Cleared by software to disable transmit interrupt requests. − Read/Set/Clear Bit 3 = SCIE Status Change Interrupt Enable Set by software to enable an interrupt request whenever the node’s status changes in run mode or whenever a dominant pulse is received in standby mode. Cleared by software to disable status change interrupt requests. Bit 2 = ORIE Overrun Interrupt Enable − Read/Set/Clear Set by software to enable an interrupt request whenever a message should be stored and no receive buffer is avalaible. Cleared by software to disable overrun interrupt requests. − Read/Set/Clear Bit 1 = TEIE Transmit Error Interrupt Enable Set by software to enable an interrupt whenever an error has been detected during transmission of a message. Cleared by software to disable transmit error interrupts. Bit 0 = ETX Early Transmit Interrupt − Read/Set/Clear Set by software to request the transmit interrupt to occur as soon as the arbitration phase has been passed successfully. Cleared by software to request the transmit interrupt to occur at the completion of the transfer. CONTROL/STATUS REGISTER (CSR) Read/Write Reset Value: 00h 7 0 BOFF EPSV SRTE NRTX FSYN WKPS 0 RUN Bit 6 = BOFF Bus-Off State − Read Only Set by hardware to indicate that the node is in bus-off state, i.e. the Transmit Error Counter exceeds 255. Reset by hardware to indicate that the node is involved in bus activities. − Read Only Bit 5 = EPSV Error Passive State Set by hardware to indicate that the node is error passive. Reset by hardware to indicate that the node is either error active (BOFF = 0) or bus-off. Bit 4 = SRTE Simultaneous Receive/Transmit Enable − Read/Set/Clear Set by software to enable simultaneous transmission and reception of a message passing the acceptance filtering. Allows to check the integrity of the communication path. 83/126 On-Chip Peripherals L9803 Reset by software to discard all messages transmitted by the node. Allows remote and data frames to share the same identifier. Bit 3 = NRTX No Retransmission − Read/Set/Clear Set by software to disable the retransmission of unsuccessful messages. Cleared by software to enable retransmission of messages until success is met. Bit 2 = FSYN Fast Synchronization − Read/Set/Clear Set by software to enable a fast resynchronization when leaving standby mode, i.e. wait for only 11 recessive bits in a row. Cleared by software to enable the standard resynchronization when leaving standby mode, i.e. wait for 128 sequences of 11 recessive bits. − Read/Set/Clear Bit 1 = WKPS Wake-up Pulse Set by software to generate a dominant pulse when leaving standby mode. Cleared by software for no dominant wake-up pulse. Bit 0 = RUN CAN Enable − Read/Set/Clear Set by software to leave standby mode after 128 sequences of 11 recessive bits or just 11 recessive bits if FSYN is set. Cleared by software to request a switch to the standby or low-power mode as soon as any on-going transfer is complete. Read-back as 1 in the meantime to enable proper signalling of the standby state. The CPU clock may therefore be safely switched OFF whenever RUN is read as 0. BAUD RATE PRESCALER REGISTER (BRPR) Read/Write in Standby mode Reset Value: 00h 7 RJW1 RJW0 BRP5 BRP4 BRP3 BRP2 BRP1 0 BRP0 RJW[1:0] determine the maximum number of time quanta by which a bit period may be shortened or lengthened to achieve resynchronization. tRJW = tCAN * (RJW + 1) BRP[5:0] determine the CAN system clock cycle time or time quanta which is used to build up the individual bit timing. tCAN = tCPU * (BRP + 1) Where tCPU = time period of the CPU clock. The resulting baud rate can be computed by the formula: 1 BR = ------------------------------------------------------------------------------------------------t CPU × ( BRP + 1 ) × ( BS1 + BS2 + 3 ) Note: Writing to this register is allowed only in Standby mode to prevent any accidental CAN protocol violation through programming errors. 84/126 L9803 BIT TIMING REGISTER (BTR) Read/Write in Standby mode Reset Value: 23h 7 0 BS22 BS21 BS20 BS13 BS12 On-Chip Peripherals 0 BS11 BS10 BS2[2:0] determine the length of Bit Segment 2. tBS2 = tCAN * (BS2 + 1) BS1[3:0] determine the length of Bit Segment 1. tBS1 = tCAN * (BS1 + 1) Note: Writing to this register is allowed only in Standby mode to prevent any accidental CAN protocol violation through programming errors. PAGE SELECTION REGISTER (PSR) Read/Write Reset Value: 00h 7 0 0 0 0 0 PAGE2 PAGE1 0 PAGE0 PAGE[2:0] determine which buffer or filter page is mapped at addresses 0010h to 001Fh. PAGE2 0 0 0 0 1 1 1 1 PAGE1 0 0 1 1 0 0 1 1 PAGE0 0 1 0 1 0 1 0 1 Page Title Diagnosis Buffer 1 Buffer 2 Buffer 3 Filters Reserved Reserved Reserved Page 0 Registers LAST IDENTIFIER HIGH REGISTER (LIDHR) Read/Write Reset Value: Undefined 7 LID10 LID9 LID8 LID7 LID6 LID5 LID4 0 LID3 85/126 On-Chip Peripherals LID[10:3] are the most significant 8 bits of the last Identifier read on the CAN bus. LAST IDENTIFIER LOW REGISTER (LIDLR) Read/Write Reset Value: Undefined 7 LID2 LID1 LID0 LRTR LDLC3 LDLC2 LDLC1 L9803 0 LDLC0 LID[2:0] are the least significant 3 bits of the last Identifier read on the CAN bus. LRTR is the last Remote Transmission Request bit read on the CAN bus. LDLC[3:0] is the last Data Length Code read on the CAN bus. TRANSMIT ERROR COUNTER REG. (TECR) Read Only Reset Value: 00h 7 TEC7 TEC6 TEC5 TEC4 TEC3 TEC2 TEC1 0 TEC0 TEC[7:0] is the least significant byte of the 9-bit Transmit Error Counter implementing part of the fault confinement mechanism of the CAN protocol. In case of an error during transmission, this counter is incremented by 8. It is decremented by 1 after every successful transmission. When the counter value exceeds 127, the CAN controller enters the error passive state. When a value of 256 is reached, the CAN controller is disconnected from the bus. RECEIVE ERROR COUNTER REG. (RECR) Page: 00h — Read Only Reset Value: 00h 7 REC7 REC6 REC5 REC4 REC3 REC2 REC1 0 REC0 REC[7:0] is the Receive Error Counter implementing part of the fault confinement mechanism of the CAN protocol. In case of an error during reception, this counter is incremented by 1 or by 8 depending on the error condition as defined by the CAN standard. After every successful reception the counter is decremented by 1 or reset to 120 if its value was higher than 128. When the counter value exceeds 127, the CAN controller enters the error passive state. Pages 1,2,3 Registers IDENTIFIER HIGH REGISTERS (IDHRx) 86/126 L9803 Read/Write Reset Value: Undefined 7 ID10 ID9 ID8 ID7 ID6 ID5 On-Chip Peripherals 0 ID4 ID3 ID[10:3] are the most significant 8 bits of the 11-bit message identifier.The identifier acts as the message’s name, used for bus access arbitration and acceptance filtering. IDENTIFIER LOW REGISTERS (IDLRx) Read/Write Reset Value: Undefined 7 ID2 ID1 ID0 RTR DLC3 DLC2 DLC1 0 DLC0 ID[2:0] are the least significant 3 bits of the 11-bit message identifier. RTR is the Remote Transmission Request bit. It is set to indicate a remote frame and reset to indicate a data frame. DLC[3:0] is the Data Length Code. It gives the number of bytes in the data field of the message.The valid range is 0 to 8. DATA REGISTERS (DATA0-7x) Read/Write Reset Value: Undefined 7 DATA7 DATA6 DATA5 DATA4 DATA3 DATA2 DATA1 0 DATA0 DATA[7:0] is a message data byte. Up to eight such bytes may be part of a message. Writing to byte DATA7 initiates a transmit request and should always be done even when DATA7 is not part of the message. BUFFER CONTROL/STATUS REGs. (BCSRx) Read/Write Reset Value: 00h 7 0 0 0 0 ACC RDY BUSY 0 LOCK Bit 3 = ACC Acceptance Code − Read Only Set by hardware with the id of the highest priority filter which accepted the message stored in the buffer. 87/126 On-Chip Peripherals ACC = 0: Match for Filter/Mask0. Possible match for Filter/Mask1. ACC = 1: No match for Filter/Mask0 and match for Filter/Mask1. L9803 Reset by hardware when either RDY or RXIF gets reset. Bit 2 = RDY Message Ready − Read/Clear Set by hardware to signal that a new error-free message is available (LOCK = 0) or that a transmission request is pending (LOCK = 1). Cleared by software when LOCK = 0 to release the buffer and to clear the corresponding RXIF bit in the Interrupt Status Register. Cleared by hardware when LOCK = 1 to indicate that the transmission request has been serviced or cancelled. Bit 1 = BUSY Busy Buffer − Read Only Set by hardware when the buffer is being filled (LOCK = 0) or emptied (LOCK = 1). Reset by hardware when the buffer is not accessed by the CAN core for transmission nor reception purposes. − Read/Set/Clear Bit 0 = LOCK Lock Buffer Set by software to lock a buffer. No more message can be received into the buffer thus preserving its content and making it available for transmission. Cleared by software to make the buffer available for reception. Cancels any pending transmission request. Cleared by hardware once a message has been successfully transmitted provided the early transmit interrupt mode is on. Left untouched otherwise. Note that in order to prevent any message corruption or loss of context, LOCK cannot be set nor reset while BUSY is set. Trying to do so will result in LOCK not changing state. Pages 4 Registers FILTER HIGH REGISTERS (FHRx) Read/Write Reset Value: Undefined 7 FIL11 FIL10 FIL9 FIL8 FIL7 FIL6 FIL5 0 FlL4 FIL[11:4] are the most significant 8 bits of a 12-bit message filter. The acceptance filter is compared bit by bit with the identifier and the RTR bit of the incoming message. If there is a match for the set of bits specified by the acceptance mask then the message is stored in a receive buffer. FILTER LOW REGISTERS (FLRx) Read/Write Reset Value: Undefined 7 FIL3 FIL2 FIL1 FIL0 0 0 0 0 0 88/126 L9803 FIL[3:0] are the least significant 4 bits of a 12-bit message filter. MASK HIGH REGISTERS (MHRx) Read/Write Reset Value: Undefined 7 MSK11 MSK10 MSK9 MSK8 MSK7 MSK6 On-Chip Peripherals 0 MSK5 MSK4 MSK[11:4] are the most significant 8 bits of a 12-bit message mask. The acceptance mask defines which bits of the acceptance filter should match the identifier and the RTR bit of the incoming message. MSKi = 0: don’t care. MSKi = 1: match required. MASK LOW REGISTERS (MLRx) Read/Write Reset Value: Undefined 7 MSK3 MSK2 MSK1 MSK0 0 0 0 0 0 MSK[3:0] are the least significant 4 bits of a 12-bit message mask. 89/126 On-Chip Peripherals Figure 42. CAN Register Map 5Ah 5Bh 5Ch 5Dh 5Eh 5Fh 60h Paged Reg1 Paged Reg1 Paged Reg0 Paged Reg1 Paged Reg2 Paged Reg1 Paged Reg2 Paged Reg1 Paged Reg2 Paged Reg3 Paged Reg2 Paged Reg3 Paged Reg2 Paged Reg3 Paged Reg4 Paged Reg3 Paged Reg4 Paged Reg3 Paged Reg4 Paged Reg5 Paged Reg4 Paged Reg5 Paged Reg4 Paged Reg5 Paged Reg6 Paged Reg5 Paged Reg6 Paged Reg5 Paged Reg6 Paged Reg7 Paged Reg6 Paged Reg7 Paged Reg6 Paged Reg7 Paged Reg8 Paged Reg7 Paged Reg8 Paged Reg7 Paged Reg8 Paged Reg9 Paged Reg8 Paged Reg9 Paged Paged Reg9 Paged Reg10 Reg8 Paged Reg9 Paged Reg10 Paged Paged Reg10 Paged Reg11 Reg9 Paged Reg10 Paged Reg11 Paged Paged Reg11 Paged Reg12 Reg10 Paged Reg11 Paged Reg12 Paged Paged Reg12 Paged Reg13 Reg11 Paged Reg12 Paged Reg13 Paged Paged Reg13 Paged Reg14 Reg12 Paged Reg13 Paged Reg14 Paged Paged Reg14 Paged Reg15 Reg13 Paged Reg14 Paged Reg15 Paged Reg14 Paged Reg15 Paged Reg15 Paged Reg15 Interrupt Status Interrupt Control Control/Status Baud Rate Prescaler Bit Timing Page Selection L9803 6Fh 90/126 L9803 Figure 43. Page Maps PAGE 0 60h 61h 62h 63h 64h 65h 66h 67h 68h 69h 6Ah 6Bh 6Ch 6Dh 6Eh 6Fh TSTR TECR RECR Diagnosis BCSR1 Buffer 1 BCSR2 Buffer 2 BCSR3 Buffer 3 Reserved Reserved Reserved Reserved LIDHR LIDLR PAGE 1 IDHR1 IDLR1 DATA01 DATA11 DATA21 DATA31 DATA41 DATA51 DATA61 DATA71 PAGE 2 IDHR2 IDLR2 DATA02 DATA12 DATA22 DATA32 DATA42 DATA52 DATA62 DATA72 PAGE 3 IDHR3 IDLR3 DATA03 DATA13 DATA23 DATA33 DATA43 DATA53 DATA63 DATA73 On-Chip Peripherals PAGE 4 FHR0 FLR0 MHR0 MLR0 FHR1 FLR1 MHR1 MLR1 Reserved Acceptance Filters Table 13. Address (Hex.) 5A 5B 5C 5D 5E 5F CAN Register Map and Reset Values Page Register Label CANISR Reset Value CANICR Reset Value CANCSR Reset Value CANBRPR Reset Value CANBTR Reset Value CANPSR Reset Value 0 CANLIDHR Reset Value CANIDHRx Reset Value CANFHRx Reset Value 7 RXIF3 0 0 0 RJW1 0 0 0 LID10 x ID10 x FIL11 x 6 RXIF2 0 ESCI 0 BOFF 0 RJW0 0 BS22 0 0 LID9 x ID9 x FIL10 x 5 RXIF1 0 RXIE 0 EPSV 0 BRP5 0 BS21 1 0 LID8 x ID8 x FIL9 x 4 TXIF 0 TXIE 0 SRTE 0 BRP4 0 BS20 0 0 LID7 x ID7 x FIL8 x 3 SCIF 0 SCIE 0 NRTX 0 BRP3 0 BS13 0 0 LID6 x ID6 x FIL7 x 2 ORIF 0 ORIE 0 FSYN 0 BRP2 0 BS12 0 PAGE2 0 LID5 x ID5 x FIL6 x 1 TEIF 0 TEIE 0 WKPS 0 BRP1 0 BS11 1 PAGE1 0 LID4 x ID4 x FIL5 x 0 EPND 0 ETX 0 RUN 0 BRP0 0 BS10 1 PAGE0 0 LID3 x ID3 x FIL4 x 60 1 to 3 60, 64 4 91/126 On-Chip Peripherals Table 13. Address (Hex.) L9803 CAN Register Map and Reset Values (continued) Page 0 Register Label CANLIDLR Reset Value CANIDLRx Reset Value CANFLRx Reset Value CANDRx Reset Value CANMHRx Reset Value CANMLRx Reset Value CANTECR Reset Value CANRECR Reset Value 7 LID2 x ID2 x FIL3 x MSB x MSK11 x MSK3 x MSB 0 MSB 0 0 6 LID1 x ID1 x FIL2 x x MSK10 x MSK2 x 0 0 0 5 LID0 x ID0 x FIL1 x x MSK9 x MSK1 x 0 0 0 4 LRTR x RTR x FIL0 x x MSK8 x MSK0 x 0 0 0 3 LDLC3 x DLC3 x 0 x MSK7 x 0 0 0 ACC 0 2 LDLC2 x DLC2 x 0 x MSK6 x 0 0 0 RDY 0 1 LDLC1 x DLC1 x 0 x MSK5 x 0 0 0 BUSY 0 0 LDLC0 x DLC0 x 0 LSB x MSK4 x 0 LSB 0 LSB 0 LOCK 0 61 1 to 3 61, 65 62 to 69 62, 66 63, 67 6E 4 1 to 3 4 4 0 6F 1 to 3 CANBCSRx Reset Value 5.7 5.7.1 CAN BUS TRANSCEIVER Introduction The CAN bus transceiver allows the connection of the microcontroller, with CAN controller unit, to a CAN bus. The transmitter section drives the CAN bus while the receiver section senses the data on the bus. The CAN transceiver meets ISO/DIS 11898 up to 1 MBaud. 5.7.2 Main Features TRANSMITTER: ■ ■ ■ ■ ■ Generation of differential Output signals Short Circuit protection from transients in automotive environment Slope control to reduce RFI and EMI High speed (up to 1Mbaud) If un-powered, L9803 CAN node does not disturb the bus lines (the transceiver is in recessive state). Differential input with high interference suppression Common mode input voltage range (VCOM) from -5 to 12V RECEIVER: ■ ■ 92/126 L9803 On-Chip Peripherals 5.7.3 Functional Description The Can Bus Transceiver is used as an interface between a CAN controller and the physical bus. The device provides transmitting capability to the CAN controller. The transceiver has one logic input pin (TX), one logic output pin (RX) and two Input/Output pins for the electrical connections to the two bus wires (CAN_L and CAN_H). The microcontroller sends data to the TX pin and it receives data from the RX pin. The transmission slew-rates of CAN_H and CAN_L voltage are controlled to reduce RFI and EMI. The transceiver is protected against short circuit or overcurrent: If ICANH and/or ICANL exceeds a current thresholds ISC, then the CAN_H and CAN_L power transistors are switched off and the transmission is disabled for TD=25µs typical. 5.7.4 CAN Transceiver Disabling function The transceiver can be disabled and forced to move in a low power consumption mode, setting CANDS bit in DCSR register. When the transceiver is in this mode it can not receive nor transmit any information to the bus. The only way to have again on board the CAN capabilities is reset CANDS bit. The CAN protocol handler can not disable nor enable the transceiver and there is no way to communicate to the controller the transceiver is down. The disabling function has the only purpose to allow the reduction of the current consumption of the device in application not using the CAN at all or using it for particular functions (such like debugging). Current consumption reduction, when disabling the trasceiver, can be as high as 15mA. Note When the CAN capabilities of L9803 are not needed additional consumption reduction can be achieved putting the CAN controller in Stand-by Mode. Figure 44. Can Bus Transceiver Block Diagram VDD OVERCURRENT ŠŠ TX0 POWER CONTROL R + RX0 − 2R R R OVERCURRENT DETECTION GND R CAN_H 2R CAN_L DETECTION 5.8 5.8.1 Power Bridge Introduction The power part of the device consists of two identical independent DMOS half bridges. It is suited to drive resistive and inductive loads. 93/126 On-Chip Peripherals L9803 5.8.2 Main Features The nominal current is 2A. The low-side switch is a n-channel DMOS transistor while the high-side switch is a pchannel DMOS transistor. Therefore no charge pump is needed. An anti-crossconduction circuit is included: the low side DMOS is switched on only when the high side is switched off and vice versa. This function avoid the two DMOS are switched on together firing the high current path from battery to ground. The function is obtained by sensing the gate voltage and therefore the delay between command and effective switch on of the DMOS doesn’t have a fixed length. The MCU controls all operations of the power stage through the BCSR dedicated register. Short circuit and overtemperature conditions are reported to the CPU using dedicated error flags. Overtemperature and short circuit conditions switch off the bridge immediately without CPU intervention. The function of the flags is independent of the operation mode of the bridge (sink, source, Z). In addition both the PWM modules can be directly connected to the power bridge. The power bridge offers then many driving mode alternatives: Direct Mode: the two half bridges are directly driven by IN1 and IN2 control bit in BCSR. PWM1 Up/Down Brake Mode: the output of PWM1 drives one side of the bridge while the other side is maintained in a fixed status. PWM1 Symmetrical Driving Mode: PWM1 line drives directly and symmetrically both side of the bridge. PWM1/PWM2 Mode: PWM1 drives one side while PWM2 drives the other (two independent half bridges). 5.8.3 Functional Description A schematic description of the Power Bridge circuit is depicted in Figure 45. In this schematic the transistors must be considered in ON condition when they gate is high (set). 94/126 L9803 Figure 45. Power Bridge Schematic VBL On-Chip Peripherals VBR UL SC_UL OVT SC_UR OVT UR OUTL OUTR DL OVT SC_DL OVT SC_DR DR PGND PGND EN bit in BCSR is the main enable signal, active high. If EN = 0, all the bridge transistors are switched off (UL, UR, DL and DR are reset) and the outputs OUTL and OUTR are in high impedance state. Being '0' the status after reset of EN, the bridge is in safe condition (OUTL=OUTR=Z). Therefore the safe condition is guaranteed in undervoltage condition (LVD reset) and in case of main clock (Safeguard reset) or software (Watchdog reset) failures. Each power DMOS has its own over current detector circuit generating SC_xx signals (see Figure 45). SC_xx signals are ORed together to generate SC flag in BCSR register. SC flag is then set by hardware as soon as one of the two outputs (or both) are short to battery, ground or if the two outputs are short together (load short). This read only bit is reset only by clearing the EN bit. The rising edge of SC causes an interrupt request if the PIE bit is set in BCSR register. When the current monitored in any of the four DMOS of the bridge exceeds limit threshold (ISC), the SC bit is set and the corresponding DMOS is switched off after tSCPI time. This function is dominant over any write from data bus by software (i. e. as long as SC is set, the bridge cannot be switched on). To switch the bridge on again the EN bit must be cleared by software. This resets the SC bit. Setting again EN, the bridge is switched on. If the overcurrent condition is still present, SC is set again (and a interrupt is generated when enabled). An internal thermal protection circuit monitors continuously the temperature of the device and drives the OVT bit in BCSR register and, in turn, the OVT signal in Figure 45. The OVT flag is set as soon as the temperature of the chip exceeds Thw and all the transistor of the bridge are switched off. This rising edge causes an interrupt request if the PIE bit is set. This read only bit is reset only by clearing the EN bit. This function is dominant over any write from data bus by software (i. e. as long as OVT is set the bridge cannot be switched on). To switch the bridge on again the EN bit must be cleared by software. This resets the OVT bit. Setting again EN, the bridge is switched on. If the overtemperature condition is still present, OVT is set again (and a interrupt is generated when enabled). 95/126 On-Chip Peripherals L9803 5.8.4 Interrupt generation Interrupt generation is controlled by PDIE bit in BCSR register. When this bit is set Overtemperature and Short-circuit conditions generate an interrupt as described in Section 5.6.3. Setting PDIE when SC and/or OVT flag are set, immediately generates an interrupt request. The interrupt request of the power bridge is cleared when the EN bit is cleared by software. 5.8.5 Operating Modes The status of the OUTL and OUTR power outputs is controlled by IN1, IN2, EN, PWM_EN and DIR bit in BCSR register, plus the PWM1 and PWM2 line, according to the Functional Description Table (Table 14). Note: The functional description table (Table 14) uses symbols UL,R (Up Left or Right) and DR,L (Down Left or Right) to indicate the driving signal of the four DMOS. Conventionally a transistor is in the on status when its driving signal is set (‘1’) while it is in off status when the driving signal is reset (‘0’). 96/126 L9803 Table 14. Functional Description Table UL DL UR DR On-Chip Peripherals Drive EN PWM_EN DIR PWM1 IN1 IN2 Operation Configuration 0 X X X X X 0 0 0 0 INHIBIT 1 0 X X 0 0 0 1 0 1 BRAKE Full or Two Half Bridges Full or Two Half Bridges Full or Two Half Bridges Full or Two Half Bridges Direct Mode 1 0 X X 0 1 0 1 1 0 BACK 1 0 X X 1 0 1 0 0 1 FORWARD 1 0 X X 1 1 1 0 1 0 BRAKE 1 PWM1 Up Brake Mode 1 0 0 0 0 1 0 1 0 BRAKE Full Bridge 1 1 0 1 0 0 1 0 0 1 FORWARD Full Bridge 1 1 1 0 0 0 1 0 1 0 BRAKE Full Bridge 1 1 1 1 0 0 0 1 1 0 BACK Full Bridge 97/126 On-Chip Peripherals Table 14. Functional Description Table (continued) UL DL UR DR L9803 Drive EN PWM_EN DIR PWM1 IN1 IN2 Operation Configuration 1 PWM1 Down Brake Mode 1 0 0 0 1 0 1 0 1 BRAKE Full Bridge 1 1 0 1 0 1 1 0 0 1 FORWARD Full Bridge 1 1 1 0 0 1 0 1 0 1 BRAKE Full Bridge 1 1 1 1 0 1 0 1 1 0 BACK Full Bridge PWM1 Symmetrical Driving Mode 1 1 0 0 1 0 0 1 1 0 BACK Full Bridge 1 1 0 1 1 0 1 0 0 1 FORWARD Full Bridge 1 1 1 0 1 0 1 0 0 1 FORWARD Full Bridge 1 1 1 1 1 0 0 1 1 0 BACK Full Bridge PWM1/PWM2 Mode 1 1 0 1 1 pwm1 pwm1 pwm2 pwm2 PWM1 ->left PWM2->right Two Half Bridges 1 1 1 1 1 pwm1 pwm1 pwm2 pwm2 PWM1 ->left PWM2->right Two Half Bridges Note: The DIR signal is internally synchronized with the PWM1 and PWM2 signals according to the selected Driving Mode. After writing the DIR bit in BCSR register, the direction changes in correspondence with the first rising edge of PWM1. The same procedure is used in the case of PWM2. This allows the proper control of the direction changes. When the PWM signal is 0% or 100%, being no edges available, the DIR bit can’t be latched and the direction does not change until a PWM edge occurs. 98/126 L9803 On-Chip Peripherals Figure 46. Example - Power Bridge Waveform, PWM Up Brake Driving Mode PWM1 DIR UL DL UR DR OUTL OUTR BRAKE BRAKE BRAKE FWD BRAKE BRAKE BACK BACK BACK 5.8.6 Register Description The power section is controlled by the microcontroller through the following register: POWER BRIDGE CONTROL STATUS REGISTER (PBCSR) Address: 0021h - Read/Write Reset Value: 00000000 7 PIE OVT SC DIR IN2 IN1 PWM_EN 0 EN Bit 0 = EN: Power Bridge enable. When reset the bridge is disabled and OUTL and OUTR are in high impedance condition. Bit 1= PWM_EN: PWM driving enable. When reset the bridge is driven directly by IN1 and IN2 bit (Direct Mode). When set the driving is made by PWM1 and/or PWM2 bit according to the Operation Mode selected by IN1 and IN2 bit. Bit 2= IN1: Left Half Bridge control bit if PWM_EN=0, driving mode selection bit if PWM_EN=1. Bit 3= IN2: Right Half Bridge control bit if PWM_EN=0, driving mode selection bit if PWM_EN=1. FWD 99/126 On-Chip Peripherals L9803 The following table summarizes the driving mode selection made by PWM_EN, IN1 and IN2 bit PWM_EN 0 1 1 1 1 IN1 X 0 0 1 1 IN2 X 0 1 0 1 Direct PWM1 Up Braking PWM1 Down Braking PWM1 Symmetrical PWM1/PWM2 Driving Mode Bit 4= DIR: Direction bit. This bit is meaningless when PWM_EN=0. When PWM_EN is set the DIR bit controls the “driving direction” of the bridge. In order to implement a precise control of the direction changes, DIR value is latched by the rising edge of the pwm signal driving the bridge. When the signal does not have edges (i.e. pwm = 0% or 100%) the DIR bit can not be latched and the driving direction does not change even changing DIR bit in BCSR. Bit 5= SC: Short Circuit flag (read only) Bit 6= OVT: Overtemperature flag (read only) Bit 7= PIE: Power section interrupt enable. 5.9 5.9.1 EEPROM (EEP) Introduction The Electrically Erasable Programmable Read Only Memory is used to store data that need a non volatile back-up. The use of the EEPROM requires a basic protocol described in this chapter. Software or hardware reset and halt modes are managed immediately, stopping the action in progress. Wait mode does not affect the programming of the EEPROM. The Read operation of this memory is the same of a Read-Only-Memory or RAM. The erase and programming cycles are controlled by an EEPROM control register. The user can program 1 to 4 bytes at the same programming cycle providing that the high part of the address is the same for the bytes to be written (only address bits A1 and A0 can change). The EEPROM is mono-voltage. A charge pump generates the high voltage internally to enable the erase and programming cycles. The erase and programming cycles are chained automatically. The global programming cycle duration is controlled by an internal circuit. 100/126 L9803 Figure 47. EEPROM Block Diagram INTERRUPT REQUEST FALLING EDGE DETECTOR On-Chip Peripherals HIGH VOLTAGE PUMP EEPCR E2ITE E2LAT E2PGM ROW DECODER 12 . . . . . . EEPROM MEMORY MATRIX 1 ROW = 4 * 8 BITS ADDRESS BUS ADDRESS DECODER 32 4*8 BITS DATA LATCHES 32 4 4 DATA MULTIPLEXER 8 8 8 bit Read amplifiers BUFFER DATA BUS 5.9.2 Functional description Read operation (E2LAT=0) The EEPROM can be read as a normal ROM/RAM location when the E2LAT bit of the CR register is cleared. The address decoder selects the desired byte. The 8 sense amplifiers evaluate the stored byte which is put on the data bus. Write operation (E2LAT=1) The EEPROM programming flowchart is shown in Figure 49. To access the write mode, the LAT with E2LAT bit has to be set by software (the E2PGM bit remains cleared). When a write access to the EEPROM area occurs, the value is latched inside the 16 data latches according to its address. When E2PGM bit is set by the software, all the previous bytes written in the data latches (up to 16) are programmed in the EEPROM cells. The effective high address (row) is determined by the last EEPROM write sequence. To avoid wrong programming, the user must take care that all the bytes written between two programming sequences have the same high address: only the four Least Significant Bits of the address can change. 101/126 On-Chip Peripherals L9803 At the end of the programming cycle, the E2PGM and E2LAT bits are cleared simultaneously, and an interrupt is generated if the IE bit is set. The Data EEPROM interrupt request is cleared by hardware when the Data EEPROM interrupt vector is fetched. Wait mode The EEPROM can enter the wait mode by executing the wait instruction of the microcontroller. The EEPROM will effectively enter this mode if there is no programming in progress, in such a case the EEPROM will finish the cycle and then enter this low consumption mode. Halt mode The EEPROM enters the halt mode if the micro-controller did execute the halt instruction. The EEPROM will stop the function in progress, and will enter in this low consumption mode. Figure 48. Data EEPROM Programming Cycle READ OPERATION NOT POSSIBLE INTERNAL PROGRAMMING VOLTAGE ERASE CYCLE WRITE OF DATA LATCHES WRITE CYCLE READ OPERATION POSSIBLE t PROG E2LAT E2PGM EEPROM INTERRUPT Figure 49. EEPROM Programming Flowchart E2LAT=0 E2PGM=0 (Read mode) E2LAT=1 E2PGM=0 Write 1 to 4 bytes in the same row (with the same 12 Most Significant Bits of the ad- Write bytes in EEPROM E2LAT=1 E2PGM=1 (Start programming cycle) Wait for end of programming (E2LAT=0 or interrupt) 102/126 L9803 On-Chip Peripherals 5.9.3 Register Description EEPROM CONTROL REGISTER (EECR) Address: 002Ch - Read/Write Reset Value: 0000 0000 (00h) 7 0 0 0 0 0 E2ITE E2LAT 0 E2PGM Bit 7:3 = Reserved, forced by hardware to 0. Bit 2 = E2ITE: Interrupt enable. This bit is set and cleared by software. 0: Interrupt disabled 1: Interrupt enabled When the programming cycle is finished (E2PGM toggle from 1 to 0), an interrupt is generated only if E2ITE is high. The interrupt is automatically cleared when the microcontroller enters the EEPROM interrupt routine. Bit 1 = E2LAT: Read/Write mode. This bit is set by software. It is cleared by hardware at the end of the programming cycle. It can be cleared by software only if E2PGM=0. 0: Read mode 1: Write mode When E2LAT=1, if the E2PGM bit is low and the micro-controller is in write mode, the 8 bit data bus is stored in one of the four groups of 8 bit data latches, selected by the address. This happens every time the device executes an EEPROM Write instruction. If E2PGM remains low, the content of the 8 bit data latches is not transferred into the matrix, because the High Voltage charge-pump does not start. The 8 data latches are selected by the lower part of the address (A bits). If 4 consecutive write instructions are executed, by sweeping from A=0h to A=3h, with the same higher part of the address, all the 4 groups of data latches will be written, and they will be ready to write a whole row of the EEPROM matrix, as soon as E2PGM goes high and the charge-pump starts. If only one write instruction is executed before E2PGM goes high, only one group of data latches will be selected and only one byte of the matrix will be written. At the end of the programming cycle, E2LAT bit is automatically cleared, and the data latches are cleared. Bit 0 = E2PGM: Programming Control. This bit is set by software to begin the programming cycle. At the end of the programming cycle, this bit is cleared by hardware and an interrupt is generated if the E2ITE bit is set. 0: Programming finished or not started 1: Programming cycle is in progress Note: Note: if the E2PGM bit is cleared during the programming cycle, the memory data is not guaranteed. Care should be taken during the programming cycle. Writing to the same memory location will over-program the memory (logical AND between the two write access data result) because the data latches are only cleared at the end of the programming cycle and by the 103/126 On-Chip Peripherals falling edge of E2LAT bit. It is not possible to read the latched data. Special management of wrong EEPROM access: If a read happens while E2LAT=1, then the data bus will not be driven. L9803 If a write access happens while E2LAT=0, then the data on the bus will not be latched. The data latches are cleared when the user sets E2LAT bit. Note: Care should be taken in the write routine: the software has to read back the data and rewrite in case of failure. 104/126 L9803 Instruction Set 6 6.1 Instruction Set ST7 Addressing Modes The ST7 Core features 17 different addressing modes which can be classified in 7 main groups: Addressing Mode Inherent Immediate Direct Indexed Indirect Relative Bit operation nop ld A,#$55 ld A,$55 ld A,($55,X) ld A,([$55],X) jrne loop bset byte,#5 Example The ST7 Instruction set is designed to minimize the number of bytes required per instruction: To do so, most of the addressing modes may be subdivided in two sub-modes called long and short: ● ● Long addressing mode is more powerful because it can use the full 64Kbyte address space, however it uses more bytes and more CPU cycles. Short addressing mode is less powerful because it can generally only access page zero (0000 - 00FFh range), but the instruction size is more compact, and faster. All memory to memory instructions use short addressing modes only (CLR, CPL, NEG, BSET, BRES, BTJT, BTJF, INC, DEC, RLC, RRC, SLL, SRL, SRA, SWAP) The ST7 Assembler optimize the use of long and short addressing modes. Table 15. ST7 Addressing Mode Overview: Mode Inherent Immediate Short Long No Offset Short Long Short Long Short Long Direct Direct Direct Direct Direct Indirect Indirect Indirect Indirect Indexed Indexed Indexed Indexed Indexed nop ld A,#$55 ld A,$10 ld A,$1000 ld A,(X) ld A,($10,X) ld A,($1000,X) ld A,[$10] ld A,[$10.w] ld A,([$10],X) ld A,([$10.w],X) 00..FF 0000..FFFF 00..FF 00..1FE 0000..FFFF 00..FF 0000..FFFF 00..1FE 0000..FFFF 00..FF 00..FF 00..FF 00..FF byte word byte word Syntax Destination Pointer Address Pointer Size (Hex.) Length (Bytes) +0 +1 +1 +2 +0 +1 +2 +2 +2 +2 +2 105/126 Instruction Set Table 15. ST7 Addressing Mode Overview: (continued) Mode Relative Relative Bit Bit Bit Bit Direct Indirect Direct Indirect Direct Indirect Relative Relative Syntax jrne loop jrne [$10] bset $10,#7 bset [$10],#7 btjt $10,#7,skip btjt [$10],#7,skip Destination PC+/-127 PC+/-127 00..FF 00..FF 00..FF 00..FF 00..FF byte 00..FF byte 00..FF byte Pointer Address Pointer Size (Hex.) L9803 Length (Bytes) +1 +2 +1 +2 +2 +3 Inherent: All Inherent instructions consist of a single byte. The opcode fully specifies all the required information for the CPU to process the operation. Inherent Instruction NOP TRAP WFI HALT RET IRET SIM RIM SCF RCF RSP LD CLR PUSH/POP INC/DEC TNZ CPL, NEG MUL SLL, SRL, SRA, RLC, RRC SWAP No operation S/W Interrupt Wait For Interrupt (Low Power Mode) Halt Oscillator (Lowest Power Mode) Sub-routine Return Interrupt Sub-routine Return Set Interrupt Mask Reset Interrupt Mask Set Carry Flag Reset Carry Flag Reset Stack Pointer Load Clear Push/Pop to/from the stack Increment/Decrement Test Negative or Zero 1 or 2 Complement Byte Multiplication Shift and Rotate Operations Swap Nibbles Function 106/126 L9803 Immediate: Instruction Set Immediate instructions have two bytes, the first byte contains the opcode, the second byte contains the operand value. . Immediate Instruction LD CP BCP AND, OR, XOR ADC, ADD, SUB, SBC Load Compare Bit Compare Logical Operations Function Arithmetic Operations Direct (Short, Long): In Direct instructions, the operands are referenced by their memory address, which follows the opcode. Available Long and Short Direct Instructions LD CP AND, OR, XOR ADC, ADD, SUB, SBC BCP Short Direct Instructions Only CLR INC, DEC TNZ CPL, NEG BSET, BRES BTJT, BTJF SLL, SRL, SRA, RLC, RRC SWAP CALL, JP Clear Increment/Decrement Test Negative or Zero 1 or 2 Complement Bit Operations Bit Test and Jump Operations Shift and Rotate Operations Swap Nibbles Call or Jump subroutine Load Compare Logical Operations Arithmetic Additions/Substructions operations Bit Compare Function Function The direct addressing mode consists of two sub-modes: Direct (short): The address is a byte, thus requires only one byte after the opcode, but only allows 00 - FF addressing space. Direct (long): The address is a word, thus allowing 64Kb addressing space, but requires 2 bytes after the opcode. 107/126 Instruction Set Indexed (No Offset, Short, Long) L9803 In this mode, the operand is referenced by its memory address, which is defined by the unsigned addition of an index register (X or Y) with an offset which follows the opcode. No Offset, Long and Short Indexed Instruction LD CP AND, OR, XOR ADC, ADD, SUB, SBC BCP No Offset and Short Indexed Instructions Only CLR INC, DEC TNZ CPL, NEG BSET, BRES BTJT, BTJF SLL, SRL, SRA, RLC, RRC SWAP CALL, JP Function Load Compare Logical Operations Arithmetic Additions/Substructions operations Bit Compare Function Clear Increment/Decrement Test Negative or Zero 1 or 2’s Complement Bit Operations Bit Test and Jump Operations Shift and Rotate Operations Swap Nibbles Call or Jump subroutine The indirect addressing mode consists of three sub-modes: Indexed (No Offset) There is no offset, (no extra byte after the opcode), and allows 00 - FF addressing space. Indexed (Short) The offset is a byte, thus requires only one byte after the opcode and allows 00 - 1FE addressing space. Indexed (long): The offset is a word, thus allowing 64Kb addressing space and requires 2 bytes after the opcode. 108/126 L9803 Indirect (Short, Long): Instruction Set The required data byte to do the operation is found by its memory address, located in memory (pointer). Available Long and Short Indirect Instructions LD CP AND, OR, XOR ADC, ADD, SUB, SBC BCP Short Indirect Instructions Only CLR INC, DEC TNZ CPL, NEG BSET, BRES BTJT, BTJF SLL, SRL, SRA, RLC, RRC SWAP CALL, JP Function Load Compare Logical Operations Arithmetic Additions/Substructions operations Bit Compare Function Clear Increment/Decrement Test Negative or Zero 1 or 2’s Complement Bit Operations Bit Test and Jump Operations Shift and Rotate Operations Swap Nibbles Call or Jump subroutine The pointer address follows the opcode. The indirect addressing mode consists of two submodes: Indirect (short): The pointer address is a byte, the pointer size is a byte, thus allowing 00 - FF addressing space, and requires 1 byte after the opcode. Indirect (long): The pointer address is a byte, the pointer size is a word, thus allowing 64Kb addressing space, and requires 1 byte after the opcode. 109/126 Instruction Set Indirect Indexed (short, long): L9803 This is a combination of indirect and short indexed addressing modes. The operand is referenced by its memory address, which is defined by the unsigned addition of an index register value (X or Y) with a pointer value located in memory. The pointer address follows the opcode. Long and Short Indirect Indexed Instructions LD CP AND, OR, XOR ADC, ADD, SUB, SBC BCP Short Indirect Indexed Instructions Only CLR INC, DEC TNZ CPL, NEG BSET, BRES BTJT, BTJF SLL, SRL, SRA, RLC, RRC SWAP CALL, JP Function Load Compare Logical Operations Arithmetic Additions/Substructions operations Bit Compare Function Clear Increment/Decrement Test Negative or Zero 1 or 2 Complement Bit Operations Bit Test and Jump Operations Shift and Rotate Operations Swap Nibbles Call or Jump subroutine The indirect indexed addressing mode consists of two sub-modes: Indirect Indexed (short): The pointer address is a byte, the pointer size is a byte, thus allowing 00 - 1FE addressing space, and requires 1 byte after the opcode. Indirect Indexed (long): The pointer address is a byte, the pointer size is a word, thus allowing 64Kb addressing space, and requires 1 byte after the opcode. Relative mode (direct, indirect): This addressing mode is used to modify the PC register value, by adding an 8 bit signed offset to it. Available Relative Direct/Indirect Instructions JRxx CALLR Function Conditional Jump Call Relative 110/126 L9803 The relative addressing mode consists of two sub-modes: Relative (direct): The offset is following the opcode. Relative (indirect): The offset is defined in memory, which address follows the opcode. Instruction Set 6.2 Instruction groups The ST7 family devices use an Instruction Set consisting of 63 instructions. The instructions may be subdivided into 13 main groups as illustrated in the following table: Load and Transfer Stack operation Increment/Decrement Compare and Tests Logical operations Bit Operation Conditional Bit Test and Branch Arithmetic operations Shift and Rotates Unconditional Jump or Call Conditional Branch Interruption management Code Condition Flag modification LD PUSH INC CP AND BSET BTJT ADC SLL JRA JRxx TRAP SIM WFI RIM HALT SCF IRET RCF CLR POP DEC TNZ OR BRES BTJF ADD SRL JRT SUB SRA JRF SBC RLC JP MUL RRC CALL SWAP CALLR SLA NOP RET BCP XOR CPL NEG RSP Using a pre-byte The instructions are described with one to four opcodes. In order to extend the number of available opcodes for an 8-bit CPU (256 opcodes), three different probate pockets are defined. These prebytes modify the meaning of the instruction they precede. The whole instruction becomes: PC-2 End of previous instruction PC-1 Prebyte PC opcode PC+1 Additional word (0 to 2) according to the number of bytes required to compute the effective address These prebytes enable instruction in Y as well as indirect addressing modes to be implemented. They precede the opcode of the instruction in X or the instruction using direct addressing mode. The prebytes are: 111/126 Instruction Set PDY 90 PIX 92 L9803 Replace an X based instruction using immediate, direct, indexed, or inherent addressing mode by a Y one. Replace an instruction using direct, direct bit, or direct relative addressing mode to an instruction using the corresponding indirect addressing mode. It also changes an instruction using X indexed addressing mode to an instruction using indirect X indexed addressing mode. Replace an instruction using X indirect indexed addressing mode by a Y one. Function/Example A=A+M+C A=A+M A=A.M tst (A . M) bres Byte, #3 bset Byte, #3 btjf Byte, #3, Jmp1 btjt Byte, #3, Jmp1 A A A A M M M M C C Dst M M M M Src H H H I N N N N N Z Z Z Z Z C C C PIY 91 Mnemo ADC ADD AND BCP BRES BSET BTJF BTJT CALL CALLR CLR CP CPL DEC HALT IRET INC JP JRA JRT JRF JRIH JRIL JRH JRNH JRM JRNM JRMI JRPL Description Add with Carry Addition Logical And Bit compare A, Memory Bit Reset Bit Set Jump if bit is false (0) Jump if bit is true (1) Call subroutine Call subroutine relative Clear Arithmetic Compare One Complement Decrement Halt Interrupt routine return Increment Absolute Jump Jump relative always Jump relative Never jump reg, M tst(Reg - M) A = FFH-A dec Y reg reg, M reg, M 0 Pop CC, A, X, PC inc X jp [TBL.w] reg, M H I M 0 N N N 1 Z Z Z C 1 N N Z Z C jrf * Jump if Port A INT pin = 1 (no Port A Interrupts) Jump if Port A INT pin = 0 (Port A interrupt) Jump if H = 1 Jump if H = 0 Jump if I = 1 Jump if I = 0 Jump if N = 1 (minus) Jump if N = 0 (plus) H=1? H=0? I=1? I=0? N=1? N=0? 112/126 L9803 Instruction Set Mnemo JREQ JRNE JRC JRNC JRULT JRUGE JRUGT JRULE LD MUL NEG NOP OR POP Description Jump if Z = 1 (equal) Jump if Z = 0 (not equal) Jump if C = 1 Jump if C = 0 Jump if C = 1 Jump if C = 0 Jump if (C + Z = 0) Jump if (C + Z = 1) Load Multiply Negate (2's compl) No Operation OR operation Pop from the Stack Function/Example Z=1? Z=0? C=1? C=0? Unsigned < Jmp if unsigned >= Unsigned > Unsigned