i think what he was trying to say is the rpi is actually quite powerful enough on its own.

after a little more refreshed reading, im inclined to thing hes right. for some reason i confused it with another board is was looking at with only 4gpio, 2 in 2 out. the rpi sees configurable enough to come close to matching the io on the traditional par port, with a theoretical clock speed that would not be a downgrade vs mach3's 100khz.

so, a rpi, a realtime clock and a break out board in a tiny box for $100-$200 would be quite viable.

the hitch now is someone needs to get software that works with it... whether its emc, mach3, or something from the ground up.

maybe its time to implement one of my ancient ideas... a web browser based UI that talks back to a nice simple motion planner and pulse generator.

couple that with xzeros new tiny low cost stepper drives and you might have something awesome and under $400 all in.