mpg

Firstly apologies, I hate having to ask a question as a first / second post but i've done a search, can't find a resolution and this is just plain annoying me! I have a MPG like the 1st picture that I want to connect to a secondary DB25 / parallel port in my dedicated CNC PC running Win XP. This...

I'm thinking of adding a MPG (Manual Pulse Generator) to my LinuxCNC PC to get me away from the keyboard and make life simpler. Has anyone added one? How hard is it to do? Do I need to change a HAL file (or something)? Which model of MPG?