OpenPLC is an effort to create a PLC-like interface to a control board, designed by the University of Nebraska, Omaha, to do HIL Simulation of PLC systems.


Currently there are no pictures uploaded.


Rev 1 Board

The system uses a PIC18F4550 as the main microcontroller. This was chosen due to the available peripherals and the low cost. The Ethernet controller is an ENC28J60, which supports 10 Mb Ethernet as an integrated Ethernet MAC + PHY.

The hardware interface is basically a bunch of op amps being used either as amplifiers or unity gain buffers with resistors to attenuate the signal.

Schematics / Layout

Available at GitHub

Note, it is not recommended that you blindly download and use the hardware yet, as the current revision still has major defects.


The software is designed to be compiled for the PIC platform using SDCC.

Source Code

Available at GitHub

Active Participants

Nicholas Wertzberger (rannick)