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From: John Savard <quadibloc@servername.invalid>
Newsgroups: comp.arch
Subject: Re: Byte Addressability And Beyond
Date: Tue, 07 May 2024 19:18:39 -0600
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On Mon, 6 May 2024 02:34:48 -0000 (UTC), Lawrence D'Oliveiro
<ldo@nz.invalid> wrote:

>On Sun, 05 May 2024 11:20:02 -0600, John Savard wrote:
>
>> If you have decimal arithmetic, there's a direct connection between how
>> numbers are represented for reading and writing, and how they are
>> represented for internal arithmetic.
>
>It is easier to do addition/subtraction if you start from the least 
>significant end and propagate the carry/borrow along.
>
>I believe those early IBM character machines worked exactly this way.

Yes, I think you're right. While the IBM 1401 did store character
strings in the conventional big-endian order, they were addressed by
the location of their least significant digit so that arithmetic could
still start there, even if it then went backwards to lower addresses.

John Savard