90-00001-A0

Features • Complete Module: – Projected Capacitive Multi Touch Controller – 2.8in LCD • Touch: – Atmel maXTouch mXT143E Touch Controller – Supports up to 8 touches • Display: – Displaytech SDT028ATFT 2.8in LCD – 320x240 resolution – 20 ms typical response time – SPI interface via ILI9341 / ILI9320 (or compatible) – Optional support for 18-bit parallel interface – White LED backlight • Cover Panel: – 1.2mm Soda Lime Glass – Optional 0.7mm Gorilla Glass™ PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 1305-4-4   Contents 1 2 Module Overview 1.1 PCB Connections 4 1.2 Debug Connector J1 5 1.3 Touch Sensor Flex Connector J2 5 1.4 Display Flex Connector J3 6 1.5 Host Connector J4 7 Overview of the 2.8in PCAP Touch Module – Atmel Xplained Configuration 4 5  2 8 2.1 Introduction 8 2.2 Understanding Unfamiliar Concepts 9 2.3 LCD Panel 9 2.4 maXTouch Capacitive Touchscreen Controller 9 2.4.1 3 4 maXTouch Controller Interface Getting Started - Atmel Xplained 9 11 3.1 Hardware Connection 11 3.2 Loading Example Code 12 3.2.1 Programming Tools 12 3.2.2 Programming the Example Code 12 3.2.3 Using the Touch Module 12 Specifications 13 4.1 Mechanical Specifications 13 4.2 Absolute Maximum Specifications 14 4.3 Recommended Operating Conditions 15 4.4 DC Specifications 15 4.5 I2C-compatible Bus Specifications 15 4.6 Power Consumption 15 4.7 Part Number 15 I2C Basics (I2C-compatible Operation) 16 5.1 Interface Bus 16 5.2 Transferring Data Bits 16 5.3 START and STOP Conditions 16 5.4 Address Byte Format 17 5.5 Data Byte Format 17 5.6 Combining Address and Data Bytes into a Transmission 18 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 1305-4-4 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 6 Revision History 19 7 Notes 20   3 1 Module Overview 1.1 PCB Connections Pin 1 Host J4 Pin 1 Touch Sensor J2 Flex J3 Display Flex Connector AT M EL MXT143E J1 Debug Pin 1 Pin 1 Figure 1 - PCB Connectors The following notations are used for pin descriptions. Note signal direction is given with respect to the touch module – not the device connected: maXTouch touchscreen LCD LCD Panel I Input only OD Open drain output O Output only, push-pull ...... P Ground or Power MXT  4 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 1305-4-4 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 1.2 Debug Connector J1 Connector J1 carries signals used to debug the MaXTouch Touchscreen Controller. Pin Type Description Pin Type Description 2 1 P +5Vdc 6 I/O I C SCL 2 - N/C 7 - N/C 3 O ~MXT_CHG 8 P GND 4 - N/C 9 O MXT DBG DATA 5 I I2C SDA 10 O MXT DBG CLK 1.3 Touch Sensor Flex Connector J2 Connector J2 connects to the touch sensor flex and carries signals used by the maXTouch controller to detect input on the touch sensor. Pin Type 1 I/O 2 I/O 3 Description Pin Type Description X1 14 I/O Y6 X3 15 I/O Y7 I/O X5 16 I/O Y8 4 I/O X7 17 I/O Y9 5 I/O X9 18 I/O Y10 6 I/O X11 19 P GND 7 P GND 20 I/O X12 8 I/O Y0 21 I/O X10 9 I/O Y1 22 I/O X8 10 I/O Y2 23 I/O X6 11 I/O Y3 24 I/O X4 12 I/O Y4 25 I/O X2 13 I/O Y5 26 I/O X0   5 1.4 Display Flex Connector J3 Connector J3 connects to the LCD panel flex and carries signals between the host and the LCD panel.  6 Pin Type 1 P 2 3 4 Description Pin Type Description Vdd 24 I/O DB8 P LED_K1 (Backlight Cathode) 25 I/O DB7 P LED_K2 (Backlight Cathode) 26 I/O DB6 P LED_K3 (Backlight Cathode) 27 I/O DB5 5 P LED_K4 (Backlight Cathode) 28 I/O DB4 6 O IM0 29 I/O DB3 7 O IM1 30 I/O DB2 8 O IM2 31 I/O DB1 9 O IM3 32 I/O DB0 10 I FMARK 33 O ~CS 11 O VSYNC 34 O WR 12 O HSYNC 35 O RS / SCL 13 O DOTCLK 36 O RD 14 O ENABLE 37 O RESET 15 I/O DB17 38 I SDO 16 I/O DB16 39 O SDI 17 I/O DB15 40 P Vcc 18 I/O DB14 41 P GND 19 I/O DB13 42 - N/C 20 I/O DB12 43 - N/C 21 I/O DB11 44 - N/C 22 I/O DB10 45 - N/C 23 I/O DB9 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 1305-4-4 2.8in PCAP Touch Module – Atmel Xplained Configuration PDA TM2800: 1.5 Host Connector J4 Pin 1 I LED_EN  24 I/O DB8  2 O LED-  25 I/O DB7  3 I SYNC 26 I/O DB6  4 - N/C 27 I/O DB5  5 - N/C 28 I/O DB4  6 I IM0  29 I/O DB3  7 I IM1  30 I/O DB2  8 I IM2  31 I/O DB1  9 I IM3  32 I/O DB0  10 O FMARK  33 I ~CS  11 I VSYNC  34 I WR  12 I HSYNC  35 I RS / SCL  13 I DOTCLK  36 I RD  14 I ENABLE  37 I RESET  15 I/O DB17  38 O SDO  16 I/O DB16  39 I SDI  17 I/O DB15  40 P Vin 18 I/O DB14  41 P GND 19 I/O DB13  42 I ~MXT_RESET  20 I/O DB12  43 O ~MXT_CHG  Pin 21 Type I/O Description DB11   22 I/O DB10  23 I/O DB9  44 45 Type I/O I Description 2  2  I C SDA I C SCL LCD MXT LCD MXT Connector J1 connects to the host and carries signals between the host and (1) the MaXTouch Touch Controller and (2) LCD Panel. NOTE: The host connector can support interfacing with the LCD panel via serial or parallel interface. Refer to the display panel datasheet s (see Section 2.2) for instructions on properly connecting unused signals if the touch module is used with hardware other than the Atmel Xplained MCU and Routing Board.   7 2 Overview of the 2.8in PCAP Touch Module – Atmel Xplained Configuration 2.1 Introduction The 2.8in PCAP Touch Module – Atmel Xplained Configuration is a touchscreen module offering best-in-class projected capacitance multi-touch functionality combined with a 2.8in LCD panel. The module is configured for development and evaluation with Atmel Xplained MCU solutions as well as development and integration with a custom host system. For convenience, this module features a host interface flex connector positioned for interfacing with an Atmel Xplained Routing Board. As shown in Figure 2 below, the module provides host access to the touchscreen controller and display interface for easy integration. PDA 2.8in PCAP Touch Module - Xplained Configuration PCB J2 J4 Capacitive Touchscreen Controller J3 LCD Panel HOST Touch sensor mXT143E Figure 2 - Functional Block Diagram  8 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 1305-4-4 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 2.2 Understanding Unfamiliar Concepts Throughout this document, the functionality of the module sub-system will be outlined and summarized. However, the user is encouraged to refer to the resources and documents below in order to gain a more thorough understanding of each sub-system. • For a basic overview of I2C communication, refer to Section 5 of this document • Displaytech SDT028ATFT Datasheet (www.displaytech-us.com) • Atmel Application Note AVR32963: mXT143E Xplained Hardware Guide (www.atmel.com) • Atmel maXTouch mXT143E Datasheet (www.atmel.com) 2.3 LCD Panel The module provides the host with a direct connection from the host (Connector J4) to the LCD panel interface (Connector J3). Aside from generating supply voltages for the LED backlight and providing backlight control to the host, no control of the display panel is performed by the module. 2.4 maXTouch Capacitive Touchscreen Controller The module touch screen interface is based on the Atmel maXTouch mXT143E Touch Controller. The touch controller scans the touch sensor and will signal the host with an active low interrupt signal (Connector J4-43 ~CHG) when new touch data is available. Data communication with the maXTouch controller is performed over a shared I2C interface (Connector J4-45 SCL and J4-44 SDA). The I2C address of the touch controller is set to 0x4A. NOTE: Pull-up resistors for the I2C SCL and SDA lines are located at R5 and R4 respectively. A pull-up resistor for the ~MXT_CHG interrupt signal is located at R7. 2.4.1 maXTouch Controller Interface Details of the maXTouch communication protocol are beyond the scope of this document. However information is provided below to facilitate evaluation and initial development. The module is pre-loaded with a configuration already optimized for this touch sensor and panel, so the developer need only focus on interfacing with the device. When developing the maXTouch controller interface during evaluation and host development, care should be taken to avoid changing the maXTouch configuration or committing changes to NV storage on the maXTouch controller. To get started with host interface development, the user is strongly encouraged to leverage existing code available from the resources outlined in the following sections. 2.4.1.1 Atmel Software Framework The Atmel Software Framework (http://asf.atmel.com) contains examples of code for interfacing with devices in the maXTouch family of touch controllers. Many of the code examples found in the ASF are targeted for this maXTouch Xplained module. 2.4.1.2 Linux Kernel / Android While the Linux or Android OS may not be applicable to all of the Atmel Xplained MCU Boards, there is a growing code base in the Linux and Android communities that can interface with maXTouch touchscreen controllers.   9 The Linux Kernel (www.kernel.org) has included basic support for maXTouch devices since version 2.6.36. The mainline driver has undergone considerable evolution since then. In addition, Atmel maintains patches (www.github.com/atmel-maxtouch/linux) which provide numerous out-of-cycle improvements to the mainline Linux Kernel driver.  10 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 1305-4-4 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 3 Getting Started - Atmel Xplained This module was designed to install on a variety of Atmel Xplained MCU boards via an mXT143E Xplained Routing Board. This configuration provides the fastest way to evaluate the performance of the touchscreen and display using Atmel Studio and example code and projects available in the Atmel Software Framework (ASF). The following sections will outline the process of installing the module on a XMEGA-A3BU Xplained. As noted in section 2.2, the user should refer to Atmel Application Note AVR32963: mXT143E Xplained Hardware Guide (www.atmel.com) for additional details on using this module with an Atmel Xplained MCU board. 3.1 Hardware Connection The module interfaces with the Xplained MCU board using connector J4 through a flex cable connector to the Atmel mXT143E Xplained Routing board. The Xplained Routing Board in turn, connects to the Atmel Xplained MCU board through connectors J1, J2, J3 and J4. Both boards have matching connectors: J1 on the Xplained Routing board connects to J1 on the Xplained MCU board, etc. Also, both boards have a corner mounting hole that is marked with a white square. The boards should be oriented so that the marked mounting hole is in the same corner. Disconnect power / USB from the Xplained MCU board before installing the touch module as shown below in Figure 3. Touch Module J1 Xplained Routing Board J2 J1 J2 Atmel Xplained MCU Board Figure 3 – Connecting the module to the Xplained MCU Board Note: that the flex cable connecting the module to the mXT143E Xplained Routing board should be inserted into each connector with the FPC contacts facing the respective board. See the illustration in Figure 4 below for more detail.   11 Flex contacts face up toward Touch Module PCB Touch Module PCB Flex Cable Xplained Routing Board J1 J2 Flex contacts face down toward Xplained Routing PCB Figure 4 – Flex Connection 3.2 Loading Example Code The user is encouraged to experiment with the various sample projects available in the Atmel Software Framework (http://asf.atmel.com). In order to demonstrate the complete functionality of the module, several of the example projects from the ASF have been compiled for the XMEGA-A3BU Xplained MCU board and binary images (HEX files) are available for download from the PDA website. See details below. 3.2.1 Programming Tools Before the example HEX files can be loaded, you must first ensure that the necessary programmer driver/software is installed on your development system. Consult the manual and/or support resources for your programmer for instructions on installation and use. 3.2.2 Programming the Example Code Download the example HEX files from http://www.pdaatl.com/modules/2.8in/mxt143xplained.zip and unzip to a working folder. Files are named according to the example project. 3.2.3 Using the Touch Module Unless noted otherwise, these example HEX files have been compiled for XMega MCU communicating with the display using USART in SPI mode – ensure that the SPI Mode Switch on the mxT143E Xplained Routing board is set to “XMEGA USART in SPI mode”  12 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 1305-4-4 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 4 Specifications For complete specifications, refer to the datasheets listed in section 2.2 for the various sub-system components outlined in Sections 2.3 and 2.4. 4.1 Mechanical Specifications Drawings and CAD models available upon request. 51.0 mm (PET Outline) Cover Panel Outline 57.13mm x 81.61mm R3.175mm in corners 1.2 mm (Cover Panel) 50.0 mm User side 70.1 mm (PET Outline) 58.6 mm (Viewable) Viewed from user side LCD side 0.460 mm (Sensor) 44.2 mm (Viewable) 0.076 mm (FPC) PIN 1 PCB contacts face down 14.1 mm 5.42 mm 13.5 mm (FPC Min Width) PIN 26 4.65 mm 43 mm (FPC Max Width) Figure 5 - Sensor Only Dimensions Sensor (P/N: 21-00001-A0) may be purchased individually. Minimum order quantities apply. Contact PDA for details.   13 46.4 mm (PCB Length) 81.82 mm (Frame Length) 1.9 mm AT M EL MXT143E 19.83 mm (Cover Panel rear surface to Mounting Boss) 7.0 mm 50.8 mm (PCB Width) 5.1 mm (PCB Component Clearance) 57.25 mm (Frame Width) Figure 6 – Module Dimensions 4.2 Absolute Maximum Specifications Parameter Value Operating temp 0oC to +70oC Storage temp -40oC to +85oC Vdd -0.5 to +3.6V Max continuous pin current, any control or drive pin ±40 mA Voltage forced onto any pin -0.5V to (Vdd + 0.5) Volts CAUTION: Stresses beyond those listed under Absolute Maximum Specifications may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or other conditions beyond those indicated in the operational sections of this specification are not implied. Exposure to absolute maximum specification conditions for extended periods may affect device reliability.  14 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 1305-4-4 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 4.3 Recommended Operating Conditions Parameter Value Vin 3.3V ±5 percent Supply ripple + noise ±20 mV 4.4 DC Specifications Vdd = 3.3, Ta = recommended range, unless otherwise noted Parameter Description Min Typ Max Units VIL Low input logic level - 0.5 – 0.3 Vdd V VHL High input logic level 0.7 Vdd – Vdd + 0.5 V VOL Low output voltage – – 0.2Vdd V VOH High output voltage 0.8Vdd – – V – – 1 µA IIL Input leakage current Notes 4.5 I2C-compatible Bus Specifications Parameter Operation Address 0x4A Maximum bus speed (SCL) 400 kHz I2C Specification Version 2.1 4.6 Power Consumption Vdd (V) Mode Idd (mA) 3.3Vdc mxt143E in free run and LCD backlight ON full. 60ma 4.7 Part Number Part Number 90-00001-A0 Description 2.8” Touchscreen Module For Atmel mXT143E Xplained   15 5 I2C Basics (I2C-compatible Operation) 5.1 Interface Bus The device communicates with the host over an I2C-compatible bus, in accordance with version 2.1 of the I2C specification. The following sections give an overview of the bus; more detailed information is available from www.i2C-bus.org. Devices are connected to the I2C-compatible bus as shown in Figure 7 both bus lines are connected to Vdd via pull-up resistors. The bus drivers of all I2C-compatible devices must be open-drain type. This implements a wired “AND” function that allows any and all devices to drive the bus, one at a time. A low level on the bus is generated when a device outputs a zero. Figure 7. I2C-compatible Interface Bus Vdd Device 1 Device 2 Device 3 Device n R1 R2 SDA SCL 5.2 Transferring Data Bits Each data bit transferred on the bus is accompanied by a pulse on the clock line. The level of the data line must be stable when the clock line is high; the only exception to this rule is for generating START and STOP conditions. Figure 8. Data Transfer SDA SCL Data Stable Data Stable Data Change 5.3 START and STOP Conditions The host initiates and terminates a data transmission. The transmission is initiated when the host issues a START condition on the bus, and is terminated when the host issues a STOP condition. Between the START and STOP conditions, the bus is considered busy. As shown in Figure 9 START and STOP conditions are signaled by changing the level of the SDA line when the SCL line is high.  16 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 1305-4-4 PDA TM2800: Figure 9. 2.8in PCAP Touch Module – Atmel Xplained Configuration START and STOP Conditions SDA SCL START STOP 5.4 Address Byte Format All address bytes are 9 bits long. They consist of 7 address bits, one READ/WRITE control bit and an acknowledge bit. If the READ/WRITE bit is set, a read operation is performed. Otherwise a write operation is performed. An address byte consisting of a slave address and a READ or a WRITE bit is called SLA+R or SLA+W, respectively. When the device recognizes that it is being addressed, it acknowledges by pulling SDA low in the ninth SCL (ACK) cycle. The most significant bit of the address byte is transmitted first. Figure 10. Address Byte Format Addr MSB Addr LSB R/W ACK 7 8 9 SDA SCL 1 2 START 5.5 Data Byte Format All data bytes are 9 bits long, consisting of 8 data bits and an acknowledge bit. During a data transfer, the host generates the clock and the START and STOP conditions. The slave device is responsible for acknowledging the reception. An acknowledge (ACK) is signaled by the slave device pulling the SDA line low during the ninth SCL cycle. If the slave device leaves the SDA line high, a NACK is signaled. Figure 11. Data Byte Format Addr MSB Addr LSB R/W ACK 8 9 Aggregate SDA SDA from Transmitter SDA from Receiver SCL from Master 1 SLA+R/W 2 7 Data Byte STOP or Next Data Byte   17 5.6 Combining Address and Data Bytes into a Transmission A transmission consists of a START condition, an SLA+R or SLA+W, one or more data bytes and a STOP condition. The wired “ANDing” of the SCL line is used to implement handshaking between the host and the device. The device extends the SCL low period by pulling the SCL line low whenever it needs extra time for processing between the data transmissions. Figure 12 shows a typical data transmission. Note that several data bytes can be transmitted between the SLA+R or SLA+W and the STOP. Figure 12. Byte Transmission Addr MSB Addr LSB R/W ACK Data MSB Data LSB ACK SDA SCL 1 START  18 2 7 SLA+R/W 8 9 1 2 7 Data Byte PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 8 9 STOP 1305-4-4 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 6 Revision History Revision No. History Rev 1209-0-1 – Sept 2012 Preliminary Draft (unreleased) Rev 1209-1-1 – Sept 2012 Initial Release (unreleased) Rev 1210-2-2 – Oct 18, 2012 Correct swapped I2C clock and data signals in Debug Connector J1 pinout table. Rev 1211-3-3 – Nov 20, 2012 Add notes to Figure 5 regarding sensor orientation and pin 1 location. Add notes to Figure 1 identifying connectors and pin 1 locations. Rev 1305-4-4 – May 30, 2013 Update references to ILI9320 to include ILI9341 LCD driver IC   19 7 Notes Precision Design Associates, Inc. 736 Johnson Ferry Rd, Suite C-270 Marietta, GA 30068 USA email: sales@pdaatl.com tel: (770)-971-4490 ® url: http://www.pdaatl.com ® ® © 2012 Precision Design Associates. All rights reserved. Atmel , Atmel logo and combinations thereof, maXTouch , QTouch , and others are registered trademarks of Atmel Corporation or its subsidiaries. Other terms and product names may be registered trademarks or trademarks of others.  20 PDA TM2800: 2.8in PCAP Touch Module – Atmel Xplained Configuration 1305-4-4