ATxmega128a1 USB Development Board

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Atmel XMEGA 128A1 (chip rev. H), 128KB flash, 8KB RAM
Onboard USB PDI programmer (no external programmer needed)
AVRISPmkII compatible
Program flash, EEPROM, fuses, lock bits, and more
Works with AVR Studio 4 and 5, AVRDUDE, Codevision, and BASCOM 2.0.6
USB - Serial Bridge
Up to 2MHz baud rate (1MHz async)
Synchronous or asynchronous operation
Optional USB ready signal
3.3V, 1A LDO regulator
Powered via USB or external header
32.768KHz crystal connected to TOSC (RTC) pins
8MHz external clock available from USB AVR
HC49 crystal landing connected to XTAL pins
Most pins routed to headers (Port A through Port K)
Solder jumpers can be used to disconnect devices when not used (frees up header pin)
MicroSD card slot with push-push spring action
32KB SPI SRAM chip
8 channel relay driver with kickback protection
Up to 70mA per channel
5V or 3.3V devices (relays, LCD backlights, etc.)
Can be used as general-purpose low-side driver
Audio amplifier connected to XMEGA DAC
Temperature sensor with low-power operation
1.25V precision voltage reference
Works with XMEGA ADC errata
Use for signed differential conversions from 0V to ~2.5V at the pin
Routed to both reference inputs via solder jumpers
4 buttons
4 LEDs
JTAG (XMEGA), PDI (XMEGA)*, and ISP (USB AVR) headers
4 boot modes selectable via jumper and button
Serial bridge (default)
AVRISPmkII compatible PDI programmer
Configuration (uses terminal emulator)
DFU bootloader (to update firmware on USB AVR via USB)
Boot button can be used to toggle between the PDI programmer and the serial bridge
Preloaded demo program demonstrates onboard peripheral devices as well as sleep mode
PCB measures 10cm x 5cm
Compatible with Windows XP/Vista/7 and Linux
All firmware is open-source (MIT license)
Uses LUFA USB library and AVRISPmkII clone by Dean Camera (


The MT-X1 is a flexible USB development board for the Atmel ATxmega128a1 microcontroller. The XMEGA can be fully programmed over USB using the onboard AVRISPmkII-compatible PDI programmer (no need to purchase an external programmer). The XMEGA can communicate with a computer using the onboard USB to serial bridge. Speeds up to 2Mbps are supported in synchronous mode (1Mbps in asynchronous mode). The Atmel AT90USB162 USB AVR, which provides these features, will automatically sleep when USB is disconnected. The board can be powered via USB or an external header. Voltage is regulated by a 3.3V, 1A LDO regulator. There are several clock options available onboard, including a 32.768KHz crystal, an external 8MHz clock, an external HC49 crystal landing, and several internal clock options. Several peripheral devices are installed and connected to the XMEGA via solder jumpers, which allows use of the pins if the device is not used. Most pins are routed to headers. These devices include a MicroSD card slot, 32KB SPI SRAM, audio amplifier, relay driver, temperature sensor, 4 buttons, 4 LEDs, and an onboard 1.25V precision reference for the ADC. This reference is setup to work with the XMEGA errata. A demo program is preinstalled on the XMEGA demonstrating use of each peripheral device, as well as demonstrating sleep mode. All software used on both the XMEGA and USB AVR is open-source (MIT license).

ATxmega128a1 Features:

High-performance, Low-power 8/16-bit AVR XMEGA Microcontroller
Non-Volatile Program and Data Memories
128K Bytes of In-System Self-Programmable Flash
8K Bytes Boot Section with Independent Lock Bits
8 KB Internal SRAM
External Bus Interface for up to 16M bytes SRAM
External Bus Interface for up to 128M bit SDRAM
Peripheral Features
Four-channel DMA Controller with support for external requests
Eight-channel Event System
Eight 16-bit Timer/Counters
4 Timer/Counters with 4 Output Compare or Input Capture
4 Timer/Counters with 2 Output Compare or Input Capture
High-Resolution Extension on all Timer/Counters
Advanced Waveform Extension on two Timer/Counters
Eight USARTs
IrDA modulation/demodulation for one USART
Four 2-Wire Interfaces w/ dual address match (I2C and SMBus)
Four SPI (Serial Peripheral Interface) peripherals
AES and DES Crypto Engine
16-bit Real Time Counter with separate Oscillator
Two Eight-channel, 12-bit, 2 Msps Analog to Digital Converters
Two Two-channel, 12-bit, 1 Msps Digital to Analog Converters
Four Analog Comparators with Window compare function
External Interrupts on all General Purpose I/O pins
Watchdog Timer with Separate On-chip Ultra Low Power Oscillator
Special Microcontroller Features
Power-on Reset and Programmable Brown-out Detection
Internal and External Clock Options with PLL and Prescaler
Programmable Multi-level Interrupt Controller
Sleep Modes: Idle, Power-down, Standby, Power-save, Ext. Stby.
Advanced Programming, Test and Debugging Interfaces
JTAG (IEEE 1149.1 Compliant)
PDI (Program and Debug Interface)
I/O and Packages
78 Programmable I/O Lines
100 - lead TQFP
Operating Voltage
1.6 - 3.6V
Speed performance
0 - 12 MHz @ 1.6 - 3.6V
0 - 32 MHz @ 2.7 - 3.6V

Last update: June 2, 2011