"Each IRD01 is connected to 1 input and 2 outputs of an RIO01. This means that an RIO01 can support 4 IRD01s (4 inputs, 8 outputs) with 4 inputs free. If the LED indicator on the IRD01 is not required or connected (RIO shunts must be set accordingly), then each RIO01 can support 8 IRD01. However, it is recommended that the LED indication on the IRD01 be used since it gives positive confirmation to the user that the IR signal was actually received."

If you have set J2-Q on the RIO to open, then, upon receiving a valid IR code, will corresponding output blink, e.g. receive IR code on input 1 will result in blinking of output 2. This means that, for the IRD01, the RX should be connected to input 1 and LED connected to output 1. The TX should not be using output 1. Rather, it should be connected to another output on the RIO which must be programmed to send out IR signals.