Need help wiring in a HY VFD to my machine...!

[12volt]

OK, couple more questions. Can you give us a picture of the output pins on the board so that we can read the labelling - if there is any. Or anything that suggests something like "analogue output" or similar. Just looking for clues here!

Also, in Mach3, one of the drop-down menus - "Plugin Control" - might have an entry which gives a clue about the type of USB board you are using. This is generally where any board-specific parameters are set up, but just knowing what the board is might help find some documentation on it.

Funny that the appropriate wires to the old VFD have disappeared, though.

Pics added, can't see anything with that label unfortunately, as as you can see from plugin control, the only option is "video window" which is obviously not anything to do with this!

Those wires haven't disappeared as such, they never existed in the first place. I'm sure there must be a setting in the VFD that allows for the kind of control we are looking at, its simply that I don't know what it is...