What is the minimum input pulse width to the CDT-TX-02M-R to cause an output from CDT-RX-02M-R?

In standby when an input is sensed, the CPU activates and waits 20ms and then samples the input (this is done on purpose to eliminate switch bounce). So the minimum input pulse width is 20ms + α.

After sampling the input, it takes about another 20ms until packet transmission begins. The time to transmit the frame and for it to be acknowledged by the receiver takes 63ms. So the total time from triggering the input until output from the CDT-RX-02M-R is 20 + 20 + 63ms = 103ms. After this point, input sampling takes place at the end of every frame, so the minimum pulse length can be 63ms.