The USC card provides 6 opto-inputs Opto_In_0..5 and 6 opto-outputs Opto_Out_0..5 on the Laser, I/O - 37 pin connector.

Unlike the Digi I/Os and the Stepper I/Os, the Opto I/Os are optical isolated. This means that the opto-circuit is galvanically isolated from the USC main power circuit.