[JerryFlyGuy]

Mach controls the G100 by sending message packets about 4 times a second. Each packet is a movement or series of movement commands which the G100 completes and then reports its completion back to mach, which sends more packets... etc..

The G100 will run one of two ways, either its under mach's control, or its not.. and there is no midway cross over for this [that I'm aware of] It's kinda like your printer, either the printer is connected to the PC and the PC operates as a print server, or you have a dedicated print server which the PC dump's to. There's no middle ground.

The reason that mach doesn't just dump everything to the G100 is because of control, in a machine tool environment, control is everything and is directly related to safety. You could argue that the G100 could report back to Mach what it's doing and what line its on etc.. but in the end you'd basically have the same system you do now, just in reverse. Having the G100 run on its own doing a repetative task is fine, when you get to machine tool operations and each is different, you need direct control w/ a proper interface.. which is the PC running Mach3.

Can you clarify the low overhead and need for speed comment? Currently the G100 will output 4Mhz of step & dir pulses per axis [thats 4 MILLION pulses on 12 pin's per second..] and will read an encoder count of 1Mhz as well. Thats pretty darn fast in my estimation... where would you like to see an improvement?

Jerry