Hello Thomas,

"building a low cost profile generator for use with machine tools. This would be used to linearly interpolate or circularly interpolate movements of two axis using a 8051 derivative. "

My gut feeling says that this will be too demanding on a 8051 core, if you plan to bring in the velocity components. Particularly on a machine tool to get at some degree of final machining accuracy, you need to resolve the position co-ordinates to atleast to 10micron level ? OK I am generalising here - if your machining involves a 10 meter component, then this level of resolution will be a overkill.

While there are methods to get away with fixed point arithmetic, the 8051 was never good or meant to do involved maths with vectors or interpolation.

The above is a general feeling ( of mine ). Can analyse more if specifics are known.

"Or is the 8051 a non-starter because of 8 bit architecture ? "

I would say so.

Raghu