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

JED AVR595 Single Board Computer using the ATmega2561

AVR256 angle photo

Dimensioned drawing: AVR595 dimensions

Parts locations: AVR595 parts.jpg

Port allocations: AVR595 ports

User's manualpdf: AVR595 User's manual

Colour schematic: AVR595 schematic

Hi-res photo: AVR595 1000.jpg

CPU Data sheet: ATMega2561

JED AVR595 "Little ozzy logger"

In summary:

  • CPU is AVR2561, with 256 Kbyte of FLASH, 8 Kbyte RAM, 4 Kbyte EEPROM;
  • LCD interface to drive Hitachi controller 2 x 40 or 4 x 20 LCD text display. Board actually can mount on back of small 4 x 20 LCD;
  • Keyboard scanner interface;
  • Back-to-back clamp diodes are placed on all user lines for ESD protection;
  • Series resistors for current and EMC limiting on all inputs;
  • Eight input ports with voltage divider resistor pairs for setting input thresholds and voltage ratios and full-scale ranges for all analog and digital inputs. Analog input is 10-bit resolution by up to 8 channels. Basic input range is 0 … 4.096 volts;
  • Two RS232 Serial ports have ESD protection and EMC filters. One port can be RS485 or V-drive USB memory port interface;
  • Ultra-stable Real Time Clock with Temperature Compensated Crystal Oscillator (TXCO) for +/- 3.5 minutes/year max error. Clock device also has a 3 degree accuracy temperature sensor as board internal temperature readout;
  • Four low level analog inputs for thermocouples, feeding a 20 bit delta-sigma ADC using LTC2492;
  • DataFlash memory providing 8 Mbyte of data storage for datalogging. Also byte-writable 32 Kbyte FRAM from Ramtron;
  • Eight N-FET output ports;
  • Four input ports to interrupts;
  • One port is a 1-Wire port for device expansion or operator certification/identification;
  • All devices used are full industrial temperature range and board is designed for lead-free manufacture.