Michael,

Thanks for the suggestion. I considered this approach as well but I am not sure it is more effiecient. A rolling buffer will require indexed access to the coefficients and old input values, as well as wrapping logic. Without a rolling buffer, it uses (hopefully) absolute addressing which doesn't require additions or index variables.

The input buffer consists of unsigned char variables, so I suspect that moving 15 bytes of memory would be quicker than anything else.

I would like to test it out, buy I am really pushing to get this project done by Monday. I'll let you know if I can take the time to try it.

- Lee