Quick Overview
* ICSP 5x2 pin connector for in-circuit programming with AVR-PG1 or AVR-PG2
* DIL20 microcontroller socket
* status LED connected to PB4
* reset IC ZM33064
* Quartz crystall oscilator circuit 10MHz
* Voltage regulator +5V, 7805 and filtering capacitors
* Power plug-in jack
* RS232 DB9 female connector , simple level shifter with transistors and diodes
* 4 optocoupler isolated inputs with screw terminals
* input status LEDs
* 4 relay outputs with 5A/250VAC contacts with screw terminals
* output status LEDs
* four mounting holes 3.3 mm (0.13")
* FR-4, 1.5 mm (0.062"), green soldermask, white silkscreen component print
* dimensions 80x100 mm (3.9 x 3.15")
