Paul,

Does Mr. Predko source this info? I never got the impression the '520 was not u-coded just more efficiently implemented between hardwire and u-code. If the '520 is not u-coded why 4 clocks? There has to be some "sequencing going on'.

The '320 and '520 where very fast at there time of introduction and really changed things as this speed was not the result of increased clock fz. The '420 is just as remarkable today. I am enjoying using the device very much.

I must admit however that i use Atmel alot both their '2051 and 'C52 as well as some AVR.

regards,
p