Ref: PC to controller comunication protocols

The desktop software sounds like it is well worth the effort. As for the
communications between the desktop and microcontroller, its a pain in the
neck there is no standard binary protocol as going from co-ordinates to
g-code on the PC, then doing it all over again in reverse on the
microcontroller is a real hindrance.
After looking through a lot of g-code files scattered around the net it seems
that very simple code, just co-ordinates and speeds, are common. Just using
the basics would make things much simpler but its not 'standard' so will
cause as many problems as it solves.
What kind of protocol are you using between the PC and PIC? I was thinking
something like simplified g-code, the axis positions and the speed with the
numbers in binary, would be the simplest and easiest to adapt to but I'm sure
there would be a lot of room for improvement.
Another thing I was leaving space for was to use two protocols side by side.
ASCII only uses the lower 128 part of each byte so there would be plenty of
space in the upper 128 for a binary protocol, then the microcontroller could
be useable with a boring old terminal and plain g-code files or run with a
bells-and-whistles desktop app without modification.
Anyway, I'm rambling on again. It sounds very interesting and well worth
continuing.
cheers.

PS. Please document the protocol to keep all us open source hippies happy :)