Re: Monroe Programmable Electronic Calculator

my high school got one in 1971 and through the punch cards,
you could get to binary &, |, and shift commands as well
as program jumps. I have a complete one in a box with
reader, manuals, unused punch cards, etc. It was an eBay
nostalgia buy a few years ago. One of these days, I will be
organized enough to have it on a table to play with it. It
was always fun to see the flashing nixie tubes as it ran
calculations.

As to the tech inside, I would expect that it was a
multi-LSI "big" chip dedicated calculator design,
so any memory was probably implemented as registers in the
chips. JUst a gues anyway.

best regards, Steve Thatcher

-----Original Message-----
>From: Brian Knittel <brianquarterbyte.com>
>Sent: Feb 28, 2008 10:58 PM
>To: cctalkclassiccmp.org
>Subject: Re: Monroe Programmable Electronic Calculator
>
>Ooooh! That's really cool. My high school had one of 
>these around 1975 or 1976, we used it before we talked
them 
>into buying an Altair. The punch card unit was pretty
spiffy,
>I think it used 8 of the row bits? And IIRC there were 
>instructions you could punch that were not available
from 
>the keyboard. The cards were the votamatic type: hanging

>chad and all. It was a lot of fun to program, and pretty

>interesting and complex for a calculator.
>
>I'd love to know what the memory technology was inside 
>-- acoustic delay, static RAM, or what?

Monroe made several type of programmable calculators most of
them were 
rebadged Compucorp's.
Based on the Compucorp HTL-chipset (a very sophistycated
bit-slice design), 
memory is mostly static ram i2102.
Several types are displayed  the oldcalculator website from
Rick Bensene.

-Rik

----- Original Message ----- 
From: "Steve Thatcher" <melamyearthlink.net>
To: "General Discussion: On-Topic and Off-Topic
Posts" 
<cctalkclassiccmp.org>
Sent: Friday, February 29, 2008 4:07 PM
Subject: Re: Monroe Programmable Electronic Calculator


> my high school got one in 1971 and through the punch
cards, you could get 
> to binary &, |, and shift commands as well as
program jumps. I have a 
> complete one in a box with reader, manuals, unused
punch cards, etc. It 
> was an eBay nostalgia buy a few years ago. One of these
days, I will be 
> organized enough to have it on a table to play with it.
It was always fun 
> to see the flashing nixie tubes as it ran
calculations.
>
> As to the tech inside, I would expect that it was a
multi-LSI "big" chip 
> dedicated calculator design, so any memory was probably
implemented as 
> registers in the chips. JUst a gues anyway.
>
> best regards, Steve Thatcher
>
> -----Original Message-----
>>From: Brian Knittel <brianquarterbyte.com>
>>Sent: Feb 28, 2008 10:58 PM
>>To: cctalkclassiccmp.org
>>Subject: Re: Monroe Programmable Electronic
Calculator
>>
>>Ooooh! That's really cool. My high school had one
of
>>these around 1975 or 1976, we used it before we
talked them
>>into buying an Altair. The punch card unit was
pretty spiffy,
>>I think it used 8 of the row bits? And IIRC there
were
>>instructions you could punch that were not available
from
>>the keyboard. The cards were the votamatic type:
hanging
>>chad and all. It was a lot of fun to program, and
pretty
>>interesting and complex for a calculator.
>>
>>I'd love to know what the memory technology was
inside
>>-- acoustic delay, static RAM, or what?
>
>
> 

> Monroe made several type of programmable calculators
most of them were 
> rebadged Compucorp's.
> Based on the Compucorp HTL-chipset (a very
sophistycated bit-slice design), 
> memory is mostly static ram i2102.
? Several types are displayed  the oldcalculator website
from Rick Bensene.

The 1700-series Monroe/Compucorp calculators is one that I
don't have a lot of information about, but I know that they
did use a very sophisticated microprocessor-like (not
bit-slice) architecture, based on the later ACL chipset,
which was an improvement over the earlier HTL chipset.  

The machines used IC-ROM-based microcode, and dynamic RAM
(not static like the 2102) for main memory.  The microcode
determined the various functions available in the machine. 
Programmable and non-programmable models were available. 
Functionality depended on the ROM board which contained the
microcode, the keyboard, and whether or not the machine
contained expanded RAM. 

The Compucorp-designed machines of this timeframe were very
advanced, and had it not been for Hewlett Packard coming out
with even more advanced (albeit larger) calculators like the
9810, 9820-series, and the 9830, then later the handheld
units like the HP-35, 45, and 65, Compucorp had, for a time,
a good share of the high-end calculator marketplace along
with HP's earlier machines (9100A, 9100B), and Wang's
calculators.

For the story of Compucorp and its machines, see my website
essay at http:
//oldcalculatormuseum.com/d-compucorp.html

Rick Bensene
The Old Calculator Museum
http://oldcalculatormu
seum.com