>  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