Atmel AVR1909

AVR1909: Display Xplained Hardware User's
Guide
Features
• 240 x 320 (QVGA) graphical TFT display
- With resistive touch
- LED Backlight
- Internal controller
• Simple SPI interface for control
• Digital (PWM) control interface for backlight
• One 40pin, 0.5mm FPC connector
• Display and backlight powered by single 3.3V
1 Introduction
The Display Xplained module gives the possibility to evaluate a 240 x 320 pixel
(QVGA) graphical RGB TFT display with a 4-wire touch interface and LED
backlight. The display is interfaced with a simple SPI interface to send and receive
commands and data. The Xplain kit provides tested low–level drivers and high-
level functions in order to get the developer quickly up to speed with his application
development.
Figure 1-1. Display Xplained evaluation module.
8-bit
Microcontrollers
Application Note
Rev. 8297A-AVR-04/10

Atmel AVR1909 Specifications

General

Architecture	AVR
Core	8-bit
Flash Memory	8 KB
RAM	1 KB
EEPROM	512 Bytes
Clock Speed	20 MHz
I/O Pins	23
ADC	10-bit
Communication Interfaces	USART, SPI, TWI (I2C)
Operating Voltage	1.8 - 5.5 V
Digital I/O Pins	23
ADC Channels	8
USART	1
SPI	1
TWI (I2C)	1
Comparators	1
Features	Watchdog Timer
Timers	3
Package	TQFP32, QFN32

Summary

1 Introduction

2 Related Items

3 General information

3.1 The LCD Module

Details the LCD module's manufacturer, model, controller, and physical attachment to the PCB.

3.2 The Touch module

Explains the 4-wire resistive touch interface, connection to MCU ADC/IO pins, and use of serial resistors.

3.3 The Backlight module

Describes the backlight system comprising three white LEDs, power connection, and current control via MOSFET.

3.4 The SPI interface

Details the simple SPI interface for LCD communication, including Chip-Select, clock, and data lines.

3.5 The SPIUSART MUX resistors

Explains the 0-ohm resistor mux for switching between regular SPI and USART master SPI modes.

3.6 The LCD Tear-Enable signal (TE)

Covers the TE signal indicating the display's scan retrace period for tear-free updates.

3.7 The LCD Reset signal

Describes the LCD reset input signal and its associated pull-up resistor for preventing unintended resets.

4 Connectors

4.1 Programming headers (J103 J104)

Details pinouts for JTAG and PDI programming/debugging interfaces on headers J103/J104.

4.2 The resistive touch pin-header (J101)

Lists pin connections for the resistive touch interface to AVR XMEGA's PORTA.

4.3 The SPITEResetbacklight pin-header (J102)

Describes pin assignments for SPI, TE, Reset, and backlight signals on header J102.

4.5 The LCD connector (J100)

Details the 40-pin FPC connector for the LCD module and its signal/power connections.

5 Available code examples and drivers

6 Mounting Display Xplained module to Xplain kit