OpenPLC is a microcontroller based small scale PLC. It uses atmega16 microcontroller and is programmed using free open source software LDmicro. All the required software, documentation and experiments can be found at:

https://github.com/FOSSEE/OpenPLC

 

 

GitHub Repositories Supporting Softwares
Main Repository Active Perl
LDmicro Repository(Windows) UnxUtils (Static Link)
LDmicro Repository(Linux using Gtk) Visual C++ 2010 Express
LDmicro Repository(Linux using Qt)