Linked Train & Train Car Control Unit v2 (LTTCC 2)
MU/Slave System used by SARR locomotives and railcars.
This shows how LTTCC works and you can grab the LTTCC microcontroller from here but if you want the microcontroller only, go to [url=https://steamcommunity.com/sharedfiles/filedetails/?id=3532121608] here [/url]
an in-depth description will come soon.