From: Clifford Heath
Organization: Open Software Associates Limited
X-Mailer: Mozilla 4.61 [en] (X11; I; Linux 2.2.17 i686)
Subject: Re: Monrobot XI
References: <3D8E5A29.B4BCE8B9@managesoft.com> <3D8E6F7C.234304F9@webaccess.net>
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NNTP-Posting-Date: Tue, 24 Sep 2002 09:36:08 EST
Date: Tue, 24 Sep 2002 09:36:04 +1000
Chuck Simmons wrote:
> Transistor computers computers go back further than you think. As early
> as 1955 or before,
Yep, I know that. In the first five years still counts as "one of the
first" in my book.
> I am wondering if Monrobot XI was really the name of a piece of software
> running in a PDP-5 or 8 (they were very similar).
Nope, built by Monroe Calculating Machine Co. Used IBM electro-mechanical
typewriters and paper tape as I/O, and also had a "Monroecard" reader
which took magnetic cards, same size as a punched card. Main storage
was on a drum which held 1024 or 2048 32-bit words - that was the "RAM"!
17ms average access time, a real speed demon.
There was a sort-of assembler but we never learned to use it, instead
typing in machine code in hexadecimal (STUVWX instead of ABCDEF as now)
after hand assembly. 3XXX was "call", TXXX was load, etc. Registers 0-7
were written 16 times around a single track on the drum to reduce read
latency to just over 1ms.
BTW there was a IC microprocessor made with the PDP-8 instruction set,
I forget the designation but had details somewhere.
Thanks Ken for the details about the Charles Babbage manual set. I had
found that too, but Minnesota is a long way from Australia :-) I hoped
to find something online.