RA8835

RAiO RA8835 Dot Matrix LCD Controller Specification Version 1.2 June 1, 2005 RAiO Technology Inc. ©Copyright RAiO Technology Inc. 2004, 2005 RAiO TECHNOLOGY INC. 1/6 www.raio.com.tw RA8835 Preliminary Version 1.2 Dot Matrix LCD Controller 1. Overview The RA8835 is a controller IC that can display text and graphics on LCD panel. It can display layered text and graphics, scroll the display in any direction and partition the display into multiple screens. It also stores text, character codes and bitmapped graphics data in external frame buffer memory. Display controller functions include transferring data from the controlling microprocessor to the buffer memory, reading memory data, converting data to display pixels and generating timing signals for the buffer memory, LCD panel. The RA8835 has an internal character generator with 160, 5 X 7 pixel characters in internal mask ROM. The character generators support up to 64, 8 X 16 pixel characters in external character generator RAM and up to 256, 8 X 16 pixel characters in external character generator ROM. 2 . Features Text, graphics and combined text/graphics display modes Three overlapping screens in graphics mode Up to 640 X 256 pixel LCD panel display resolution Programmable cursor control Smooth horizontal and vertical scrolling of all or part of the display 1/2-duty to 1/256-duty LCD drive Up to 640 X 256 pixel LCD panel display resolution memory 160, 5 X 7 pixel characters in internal maskprogrammed character generator ROM Up to 64, 8 X 16 pixel characters in external character generator RAM Up to 256, 8 X 16 pixel characters in external character generator ROM 6800 and 8080 family microprocessor interfaces Low power consumption—3.5 mA operating current (VDD = 3.5V), 0.05 μA standby current Package: RA8835P3N: QFP-60 pin (Lead Free) RA8835P4N: TQFP-60 pin (Lead Free) Power: 2.7 to 5.5 V 3 . Block Diagram V A [1 5 :0 ], V D [7 :0 ], VCE, VRD, VW R TEST 2 5 6 B yte CGROM D is p la y R A M I/F S ys te m C o n f ig u r e R e g is t e r s B lo c k C u rs o r C o n t r o lle r D a ta L a tc h MCU I/F X ’t a l OSC T im in g G e n e ra to r D [7 :0 ], C S , R D , W R A0, R ES, SEL1, SEL2 XD XG Y D IS , L P , W F , X S C L , Y D , Y S C L , X D [3 :0 ] RAiO TECHNOLOGY INC. 2/6 www.raio.com.tw RA8835 Preliminary Version 1.2 Dot Matrix LCD Controller 4. Package XG SEL1 SEL2 WR RD NC NC RES VRD VCE VWR VA0 VA1 VA2 VA3 VA4 VA5 VA6 VA7 VD4 VD5 VD6 VD7 YSCL YD YDIS WF LP GND XSCL SECL XD0 XD1 XD2 XD CS A0 VDD D0 D1 D2 D3 D4 D5 D6 50 45 40 35 RAiO 60 1 Index TM 30 VA8 VA9 VA10 VA11 VA12 VA13 TEST VA14 VA15 VD0 VD1 VD2 45 RA8835P3N 05xx Date Code(Year 2005) 29 5 6 25 20 10 15 VD3 VD2 VD1 VD0 VA15 VA14 VA13 VA12 VA11 VA10 VA9 VA8 VA7 VA6 NC 46 31 30 RAiO TM RA8835P4N 05xx Index 60 1 Date Code(Year 2005) 16 15 XD3 D7 D6 D5 D4 D3 D2 D1 D0 VDD A0 CS XD XG SEL1 D7 XD3 XD2 XD1 XD0 XECL XSCL GND LP WF YDIS YD YSCL VD7 VD6 VD5 VD4 VD3 Figure 4-1: RA8835P3N(QFP-60 Pin) Figure 4-2: RA8835P4N (TQFP-60 Pin) 5 . Pin Descriptions 5.1.1. MCU Interface Pin Name D0 to D7 Function MCU Data Bus. Tri-state input/output pins. Connect these pins to an 8- or 16-bit microprocessor bus. MCU Interface Select. The RA8835 series supports both 8080 family processors (such as the 8085 and Z80®) and 6800 family processors (such as the 6802 and 6809). SEL1 SEL1, SEL2 0 1 SEL2* 0 0 Interface 8080 family 6800 family A0 A0 A0 RD RD E SEL1 should be tied directly to VDD or VSS to prevent noise. If noise does appear on SEL1, decouple it to ground using a capacitor placed as close to the pin as possible. Read Control or Enable. When the 8080 family interface is selected, this signal acts as the active-LOW read strobe. The RA8835 series output buffers are enabled when this signal is active. When the 6800 family interface is selected, this signal acts as the active-HIGH enable clock. Data is read from or written to the RA8835 series when this clock goes HIGH. RD or E RAiO TECHNOLOGY INC. 3/6 VS5 VA4 VA3 VA2 VA1 VA0 VWR VCE VRD RES NC NC RD WR SEL2 WR WR R/ W CS CS CS www.raio.com.tw RA8835 Preliminary Version 1.2 Dot Matrix LCD Controller Write Control or Read/Write Control. When the 8080 family interface is selected, this signal acts as the active-LOW write strobe. The bus data is latched on the rising edge of this signal. When the 6800 family interface is selected, this signal acts as the read/write control signal. Data is read from the RA8835 series if this signal is HIGH, and written to the RA8835 series if it is LOW. Chip Select. This active-LOW input enables the RA8835 series. It is usually connected to the output of an address decoder device that maps the RA8835 series into the memory space of the controlling microprocessor. Command/Data Select. 8080 Family Interface: WR or R/ W CS A0 0 1 0 1 RD 0 0 1 1 WR 1 1 0 0 A0 Function Status flag read Display data and cursor address read Display data and parameter write Command write 6800 Family Interface: A0 0 1 0 1 R/ W 1 1 0 0 E 1 1 1 1 Function Status flag read Display data and cursor address read Display data and parameter write Command write RES Hardware Reset. This active-LOW input performs a hardware reset on the RA8835 series. It is a Schmitt-trigger input for enhanced noise immunity; however, care should be taken to ensure that it is not triggered if the supply voltage is lowered. 5.1.2 Display Memory Control The RA8835 series can directly access static RAM and PROM. The designer may use a mixture of these two types of memory to achieve an optimum trade-off between low cost and low power consumption. Pin Name Function 16-bit Display Memory Address. When accessing character generator RAM or ROM, VA0 to VA3, reflect the lower 4 bits of the RA8835 row counter. Display Memory Data Bus. 8-bit tri-state display memory data bus. These pins are enabled when VRD or VWR is LOW. Display Memory Write Control. Active-LOW display memory write control output. Display Memory Read Control. Active-LOW display memory read control output. VA0 to VA15 VD0 to VD7 VWR VRD RAiO TECHNOLOGY INC. 4/6 www.raio.com.tw RA8835 Preliminary Version 1.2 Dot Matrix LCD Controller VCE Display Memory Chip Select. Active-LOW static memory standby control signal. VCE can be used with CS . 5.1.3 LCD Drive Signals In order to provide effective low-power drive for LCD matrixes, the RA8835 series can directly control both the X- and Y-drivers using an enable chain. Pin Name Function Data Output for Driver. 4-bit X-driver (column drive) data outputs. Connect these outputs to the inputs of the X-driver chips. Latch Clock. The falling edge of XSCL latches the data on XD0 to XD3 into the input shift registers of the X-drivers. To conserve power, this clock halts between LP and the start of the following display line (See section 6.3.7). Trigger Clock for Chain Cascade. The falling edge of XECL triggers the enable chain cascade for the X-drivers. Every 16th clock pulse is output to the next X-driver. Latch Pulse. LP latches the signal in the X-driver shift registers into the output data latches. LP is a falling-edge triggered signal, and pulses once every display line. Connect LP to the Y-driver shift clock on modules. AC Drive Output. The WF period is selected to be one of two values with SYSTEM SET command. Latch Clock for YD. The falling edge of YSCL latches the data on YD into the input shift registers of the Y-drivers. YSCL is not used with driver ICs which use LP as the Y-driver shift clock. Data Pulse Output for Y Drivers. It is active during the last line of each frame, and is shifted through the Y drivers one by one (by YSCL), to scan the display’s common connections. Power-down Output Signal. YDIS is HIGH while the display drive outputs are active. YDIS goes LOW one or two frames after the sleep command is written to the RA8835 series. All Ydriver outputs are forced to an intermediate level (de-selecting the display segments) to blank the display. In order to implement power-down operation in the LCD unit, the LCD power drive supplies must also be disabled when the display is disabled by YDIS. XD0 to XD3 XSCL XECL LP WF YSCL YD YDIS 5.1.4. Oscillator and Power Pin Name Function Crystal Connection for Internal Oscillator This pin can be driven by an external clock source that satisfies the timing specifications of the EXT f0 signal (See section 7.3.6). Crystal Connection for Internal Oscillator Leave this pin open when using an external clock source. 2.7 to 5.5V Supply. This may be the same supply as the controlling microprocessor. XG XD VDD RAiO TECHNOLOGY INC. 5/6 www.raio.com.tw RA8835 Preliminary Version 1.2 Dot Matrix LCD Controller Ground Test Pin. TEST This is a test pins. No need for connection(NC). Note: The peak supply current drawn by the RA8835 series may be up to ten times the average supply current. The power supply impedance must be kept as low as possible by ensuring that supply lines are sufficiently wide and by placing 0.47μF decoupling capacitors that have good high-frequency response near the device’s supply pins. GND 6 . System Application SRAM LCD Driver MCU RA8835 LCD Driver LCD Panel RAiO TECHNOLOGY INC. 6/6 www.raio.com.tw