Namco "RAYS" gun i/o board emulator.
Partially emulates rare Namco gun I/O, code name "RAYS".
See this thread: https://forums.arcade-museum.com/threads/wtb-namco-rays-i-o-pcb.477560/
I/O board speaks JVS, uses a b/w camera to track IR laser dot, emitted by the "gun". Used in some Deluxe versions of games like "Time Crisis" and "Crisis Zone".
This "emulator" in action: https://www.youtube.com/watch?v=khpfPEXcfk8