JED Micro
Designers and manufacturers of industrial and audio/visual controllers in Australia

JED AVR256 Single Board Computer using the ATmega2560

AVR256 angle photo

The detailed specification of this card is downloadable as a pdf: AVR256 spec

A dimensioned drawing is available as a pdf: AVR256 dimensions

Layout drawing as a JPG file: Functions of AVR256.jpg

Port allocations and functions document pdf: AVR256 ports

Hi-res photo of AVR256 board: AVR256.jpg

CPU Data sheet: ATMega2560

JED AVR256 standard architecture for ATmega2560 applications

The ATmega2560 is a standard ATmega core CPU with 8K RAM, 256K FLASH, 4K of EEPROM and is in a 100 pin package. It has 4 serial UARTs, I2C and SPI interfaces, and 86 I/O lines. The full device data-sheet is 449 pages long, and is available at

The JED ATmega2560 board is an example of a CPU applications board for general use using this CPU, but differs dramatically from the usual board sold by microprocessor companies, in that all the inputs and outputs are industrial interfaces. This is an industrial-strength board, useable in real-world applications:

Flexible memory expansion is provided: CPU RAM can be expanded to 64 Kbyte, a 32Kbye non-volatile FRAM and a 8/16 Mbyte DataFlash provide non-volatile data logging memory, and an optional SD/MMC interface can provide many Mbytes of removable data logging memory. Optional host USB connection is available to “USB Memory Sticks”.

Com ports

The Standard configuration of serial ports is shown in the photo (above), where the four RS232 four black 10-pin IDC connectors can be seen across the top of the board. (This photo also shows the XPort device which is an option on Com 1.)

This photo also shows the four-pin connector(J29) loaded in place of the SD/MMC connector which adds three more input lines, including an external interrupt and T3/Int6.

Four serial ports with flexible loading of interfaces for the four CPU UARTs is provided, so as well as RS232 on all four ports, options allow for:

Flexible power control compatible with 12 volt vehicle or solar powered and battery powered systems is provided, allowing systems to auto-start from a real-time-clock alarm, or from an external event such as an ignition turn-on in a vehicle. (Customised versions of this board could have protection and switching regulators for 24 volt vehicle environments.) Communication devices and ports can be powered up and down under program control.