hp proprietary uP history

From: Bill McDermith <bill_mcdermith_at_mcdermith.net>
Date: Fri Apr 30 01:40:05 2004

Al Kossow wrote:
> I was wondering how much information is around on the
> microprocessors HP built in the late 70's/early 80's
>
> I found some information on the MC2 in the Osborne processor
> books from '79, and it appears an MC5 is used as the maint
> processor in the HP3000 Series 44.
>
> Anyone know what processor is used in the HP64000? One note
> on Usenet claimed it was an Inmos part?

Actually, it used the BPC processor, which is the CPU part of
the mutli-chip set used in the 9825 calculator. The BPC was a
cross between the hp2100 instruction set and the 21MX instruction
set. It had byte-addressable instructions, and a return stack
with a JSB variant that would push the return address on the
stack instead of the first word of the target subroutine
(necessary if the program was in rom...)

Initially there were some development tools on the HP3000,
but by the time I had started to work on it, there was
a Pascal compiler and assembler on the 64000 itself that
would target it, and we only used the 3000 for the parser
generator used to handle the function keys.

Pretty sure it was manufactured somewhere in California,
the guys making calculators would be a good bet...

Don't think I have a BPC manual around, but I'll take a look...

Bill McDermith
Received on Fri Apr 30 2004 - 01:40:05 BST