Design a PCB using ATxMega32A4U-AU (1.8-3.6V) micro, with 4 x digital inputs that will implement 4 x pulse counters incrementing when connected to a reed switch. The unit should be powered by voltage of 5-15VDC. It should also have 1 x RS485 Port (3.3V Device) with Modbus protocol implemented that will allow access to the 4 Pulse counters. the counter values should be stored in non-volatile storage (eeprom or other). PCB size to be +- 70mm x 30mm. Connectors RJ11. Device address startup as default, and Modbus command to change the default.
Software to be written in C - Winavr AVR studio.