Extremely CISC instructions

Chuck Guzis cclist at sydex.com
Wed Aug 25 11:45:50 CDT 2021

On 8/25/21 9:27 AM, Todd Goodman via cctalk wrote:

> Nope, the standard doesn't specify those bit sizes.
> Back in the 80s I was using the BBN C Machine with 10-bit bytes and
> happily building from source I picked up on the newsgroups with little
> issue

Or, you could simply be bit-addressable, like the aforementioned
STAR-100.  This works to great advantage on vector machines, where
control vectors are usually bit arrays.

The downside is that when reading dumps, you had to do a lot of mental
shifting to convert from addresses to indices.   We had an SR-22 in the
machine room to help out.

There were many word-addressable machines also.   A byte was whatever
your shifting or masking made of it.   The UNIVAC 1100 series was
interesting in that a 36-bit word could be divided up by the hardware in
6, 9 or 12 bit parcels.


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