P8031AH MPU part substitution

[Gregg]

It is getting harder and harder to find P8031AH's.   After reading MCS® 51 Microcontroller Migration- HMOS TO CHMOS, I decided to take a gamble in the interest of science and purchased a few P80C31BH's from Jameco to see if an MP-2 would work using one.  I dropped a P80C31BH into a known working MP-2 and it worked just fine.

Figured folks would like to know this.

Gregg

[rnolan]

Hey Gregg, that's great news

So what do these thingys do and what's the difference in the new ones?

[Gregg]

This is the MP-2's CPU, microcontroller, or MPU (all synonyms). It is the "brain" of the MP-2. The newer part is made with a different manufacturing process which changes some of the electrical characteristics of the CPU for the better in a backwards compatible way.  One "feature" is that it consumes less power, but that isn't a significant benefit for the MP-2 since it is mains powered.  There are also some other features that were added, but are of no consequence as the MP-2 doesn't need or use them.

Gregg

[MarshallJMP]

You can also use the 8051 or 80c51 and maybe even the atmel 89C51 but not sure about that one. Maybe I'll try it out, I think I have some 89C51 lying around.