Thank you all for the replies. There does seem to be some confusion though, although I thought it was clear in my 1st post - the first purchase the 'Mach3' pendant was / is supposedly a USB device and was supposed to use Mach3 Modbus? , the other is a wired device intended for a DB25 parallel connection and this one came with the 22 pin schematic and little else.
As requested i've taken the backs off to show the insides - the 'USB' unit clearly has +5v, 0v, A and B outputs to the USB connection. All components are in picture other than LEDs and two push button switches on reverse. The IC has no markings so cannot be identified but my limited electronics knowledge says there are two crystals on board - maybe to provide the pulse stream? The second unit is again clearly the wired for DB25 device. Other than the switch on the side, it is pretty much restricted to 6 pole encoder (the other unit has a 4 pole encoder) and two multi position switches that follow the wiring schematic.
@joeaverage - if you made a wired pendant from a USB P1A - a picture of the inside of that may prove enlightening and what PlugIn did you then use to operate it with Mach3.
What I find frustrating with YouTube videos showing many variations of pendant usage is they either use proprietary software / plugin's for some obscure CNC or if it is Mach3, its a case of plug it in to PC / Laptop and hey presto - it works ! ! ! with no details of how? This is the most enlightening webpage tutorial that explains a lot (at least to me anyway!)
https://whyelectricshock.wordpress.c...s-milling-cnc/ The video on YT is good but I can't link two URL's in a single post!