Sujet : Re: On Binary Digits
De : dnomhcir (at) *nospam* gmx.com (Richmond)
Groupes : comp.miscDate : 12. May 2025, 19:56:06
Autres entêtes
Organisation : Frantic
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anthk <
anthk@openbsd.home> writes:
On 2025-04-04, Lawrence D'Oliveiro <ldo@nz.invalid> wrote:
On 02 Apr 2025 16:45:38 GMT, Aharon Robbins wrote:
>
Octal was used heavily on the PDP-11, if you used the assembler.
>
All DEC’s systems used octal heavily, prior to the VAX. That’s when they
started using hex.
>
All the DEC machines prior to the PDP-11 had word lengths that were
multiples of 3 (12, 18, 36), so octal worked nicely. Even though the
PDP-11 was a 16-bit machine, fields in its instruction format were still
designed to line up with octal digits.
>
Why? "octal" means base eight ( as 'ocho' in Spanish, same Latin root).
>
forth>3 8 lcm .
>
24
>
Not very fitting for a 36 bit machine except for opcodes.
Octal numbers are 3 bits per digit, and 36 divides by 3.
On Binary Digits
Re: On Binary Digits
