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From: John Savard <quadibloc@servername.invalid>
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Subject: Re: Byte Addressability And Beyond
Date: Sun, 05 May 2024 11:20:02 -0600
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On Wed, 1 May 2024 00:09:28 -0000 (UTC), Lawrence D'Oliveiro
<ldo@nz.invalid> wrote:

>Big-endian 
>supposedly had the advantage of making memory dumps easier to read, but 
>little-endian always made more logical sense.

There is one practical argument for big-endian encoding.

Let us suppose that a computer has the ability to do *both* decimal
arithmetic and binary arithmetic.

So a word in the computer might contain just bits, for binary
arithmetic. Or it might contain BCD digits, for decimal arithmetic.

Since it's possible to design an adder where carrying early between
nibbles can be turned on or off, on for decimal arithmetic, and off
for binary arithmetic, clearly the order of digits - big-endian or
little-endian - should be the same between binary and decimal.

Also, though, for ease of conversion, the order of BCD digits _should
be the same as the order of the characters of which these digits are
the last four bits_ in the representation of a decimal number as a
character string.

And that means big-endian.

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.

John Savard