I would like to drive from the Relay outputs on the controller directly, using the FWD and REV outputs to drive two separate LEDs e.g. green for FWD and red for REV. Is it possible to drive LEDs directly from the Relay FWD / REV outputs? Is there any good technical reference that explains the FRC Controller’s Relay output signal drive characteristics, i.e. voltage and max current source/sink per output channel? For a LED drive capability like I describe, what would IFI recommend as the appropriate drive current for the LEDs that is safely within the capabilities of the Relay output channels?
Yes, it is possible to drive LEDs directly from the Relay FWD / REV Outputs. Connect the anode of the LED to the FWD or REV Output. Connect the cathode of the LED to ground. The outputs can sink and source at least 8 mA. There is a 330 ohm series resistor between the VHCT logic outputs and each the FWD and REV header posts. Assuming the LEDs you are using can handle 15 mA of continuous current, direct connect them as described above.