> I 'm trying to get my head around a 10-bit machine optimised for C.

How about 23-bits? That was one of the early ESS machines, evidently

optimized to make every bit count. (Maybe a prime wordwidth helps

with hashing?)

Whirlwind II (built in 1952), was 16 bits. It took a long while for that

to become common wisdom.

Doug

On Tue, Feb 2, 2021 at 10:32 PM Dave Horsfall <dave@horsfall.org> wrote:

On Tue, 2 Feb 2021, Richard Salz wrote:

> BBN made a machine "optimized" for C. It was used in the first
> generation ARPAnet gateways.
>
> A word was 10bits. The amount of masking we had to do for some portable
> software was unreal.

I'm trying to get my head around a 10-bit machine optimised for C...
Well, if you accept that chars are 10 bits wide then there shouldn't be
(much of) a problem; just forget about the concept of powers of 2, I
guess.

Shades of the 60-bit CDC series, as handling strings was a bit of a
bugger; at least the 12-bit PDP-8 was sort of manageable.

-- Dave