Is The Test Command Supported by Onkyo AVR?

Reading on the Denon sub that there is a "Test" command that can be used to send valid commands to the AVR. I tried it on my Onkyo TX-NR777 and it did not work. I sent a known good command AV|1~Source~PC as AV|1~Test~Source~PC and nada (no change in input from STRM BOX to PC). I'm using the "Onkyo Driver Command Testing" function to send the command and I receive the message that the server has sent the command. What am I doing wrong or is this not supported by Onkyo? Appreciate any assistance as I stumble along, thanks.