Hi Guys - i'm not a frequent visitor as i'm usually able to resolve problems myself but this is stumping me completely, probably due to my lack of electronics understanding!

I bought a 'Chinese' MPG marked as suitable for Mach3 and it came with a USB plug which when plugged in, powers the device, flashing LEDs that change in response to switch positions and movement of the handwheel BUT it doesn't show up anywhere in Mach3 although 'Device Manager' sees it as connected to Port 3. There were no included instructions so I sort of gave up! (picture of unit attached)

I then recently checked out a few YouTube vids that showed MPG's being used with Mach3 so I had another search and bought a different unit, this one looking like it would use a parallel port connection (second picture)
From YT video I obtained one wiring diagram (pic 3) and with the MPG a separate schedule (of which, what is supposed to go where is a mystery)(pic 4)

So what I need is (in really short words and sentences) if I follow pic 3 and connect the MPG to a parallel plug where does this get plugged into, as my set up is PC with parallel port - cable to - Gecko G540 - Stepper motors. It would appear if the PC is disconnected the MPG would have to drive the Gecko but without power? Do I need a BOB to go between that will have 'two inputs', one from PC, the other from the MPG that will output to the Gecko ?

Whilst reading the Mach2 manual it referenced a 'key grabber' contained within Mach to facilitate connection of encoders / MPG's but didn't really elaborate for the electrically incompetent like me! I can glue wires together if I know where they are supposed to go and can select devices and answer simple queries but all this 'seems' way harder than it needs to be (to me at least!)

Ian.