Xref: utzoo comp.arch:8643 comp.sys.hp:1668
Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ncar!cruff
From: cruff@ncar.ucar.edu (Craig Ruff)
Newsgroups: comp.arch,comp.sys.hp
Subject: Re: Was *this* the first RISC chip?
Keywords: Hewlett-Packard, microprocessor, RISC
Message-ID: <1532@ncar.ucar.edu>
Date: 7 Mar 89 15:58:28 GMT
References: <1068@cantuar.UUCP>
Reply-To: cruff@handies.UCAR.EDU (Craig Ruff)
Organization: Scientific Computing Division/NCAR, Boulder CO
Lines: 24

In article <1068@cantuar.UUCP> greg@cantuar.UUCP (G. Ewing) writes:
>During a recent fit of idle curiosity, I came across some articles
>describing the microprocessor used in many of HP's handheld
>calculators from the HP-35 on.
>... Ideally I'd like enough info to write a
>simulator for it (okay, so I'm wierd). The articles I have (from
>the HP Journal) don't go into much detail.

Ah yes.  When I was a college student with nothing better to do,
I wrote just such a simulator for the HP-41C.  I got the description
of the processor and the ROM listings from the newsletter of that
calculator club (I forget the name exactly) that dug into the guts
of programmable calculators to see what was there.

Anyway, I programmed it on an HP 9825 desktop (one line display!) we
had in the chem lab.  I had to type in all of the instructions in hex
by hand (a few K!).  I got it to the point where it would
actually do stuff like the calculator would.  Too bad I didn't make
copies of the articles and the code and data files.  I could have
put it on much more powerful computers! :-)
-- 
Craig Ruff      NCAR                         INTERNET: cruff@ncar.UCAR.EDU
(303) 497-1211  P.O. Box 3000                   CSNET: cruff@ncar.CSNET
		Boulder, CO  80307               UUCP: cruff@ncar.UUCP