Polymodular CPUs

[Chris MacDonald]

> >The 6502 is still available in the US from Jameco Electronics. The 1mHz
> version is $3.25 in single pieces.

Not to take anything away from this fine CPU, but if a "start from scratch"
design is decided upon, perhaps the 68000 should be considered instead?

This is a great CPU IMHO, it powered the original Amigas as well as the Sega
Genesis video game system.  It is far superior to the 6502 in many ways,
such as: a lot more registers - all 16 bit, larger instruction set, better
addressing modes, faster clock speeds.  Better than anything Intel had in
it's day too (he says, diving for cover).  I believe Hal Chamberlin has a
section on the 68000 in his book and says good things about it. The 8mhz
version can be had for around $7 U.S. from Jameco.

I have never built a computer system using one so I can't say how many
support chips it requires or how tricky the hardware design would be, it's
definitely not an "all-in-one" microcontroller though.

I have written a lot of assembly code for it (more than 5 years though) and
it is easy to program.  There's probably a 68000 GNU C compiler around as
well.

Just my two cents.

-Chris