Actually, the 16F610 only has 64 bytes of ram.

So it's similar to the 16F676, which I added up the bytes used for in this thread ...
http://www.picbasic.co.uk/forum/show...7128#post97128

ASM handlers are the way to go on those memory challenged parts.

There are 3 versions of SPWM. (SSPWM, Multi-SSPWM and SPWM_INT).
They should all work, as they are all ASM type interrupts.

DT