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Newsgroups: comp.lang.ada
Date: Fri, 24 Jan 2020 07:01:54 -0800 (PST)
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Subject: Re: Creating several types from a base type and conversion
From: Ken Roberts <alisonken1@gmail.com>
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Xref: reader01.eternal-september.org comp.lang.ada:57934
Date: 2020-01-24T07:01:54-08:00
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On Friday, January 24, 2020 at 4:38:53 AM UTC-8, Optikos wrote:

<snip>

OK - here's what I'm looking at.

Based upon the hardware I worked on (and documentation for the 642 system), apparently it's BE based:

Register representation on panel: R bits 29 .. 0

where MSB is on the left and LSB on the right.

Memory is 30 bits (just like registers) and is physically spread over 5 chassis with 6 bits of each word stored on each chassis:

chassis 1 : bits 5 .. 0
chassis 2 : bits 11 .. 6
chassis 3 : bits 17 .. 12
chassis 4 : bits 23 .. 18
chassis 5 : bits 29 .. 24

If you look up to my third post you can see the basic setup of how a word is interpreted for instructions, with all calculations based on the msb .. lsb concept.