Hypertherm Phoenix 8.0 - Manual (Page 318)

Diagnostics
311
Expanded I/O
For controls equpped with more than 64 I/O, a series of selection softkeys are available to
access the required inputs, ouputs and analog I/O.
Note: The optional USB Front Panel I/O is not accessible from the I/O Diagnostics
screen. Functionality for the USB Front Panel can be tested through the Keyboard
Diagnostics.