I hadn't made the connection before

Chuck Guzis cclist at sydex.com
Fri Jun 2 11:26:46 CDT 2017


On 06/02/2017 07:55 AM, Al Kossow via cctalk wrote:

> 
> A very odd version of the PDP-11
> 
> I did some programming on it for GI in the late 70's using their
> GIMINI development system and cross-development tools on their Sigma
> 9.

I sold a bare CP1600 chip about a year ago to a collector.   "Odd" is an
understatement. A 10-bit wide instruction word, with the upper 6 bits of
the opcode unused.   Loading a 16-bit address took three words.

Also, slow, very slow, with no I/O instructions.   A stripped-down
instruction set (IIRC, exclusive OR and AND Boolean ops, but no
inclusive OR).  We'd examined its possible usage, but determined that
code would run slower on it than on most contemporary 8-bit CPUs.

But, for 1975, notable because it's a 16-bit monolithic CPU among a
handful of others (Fairchild 9440, MicroNova, National PACE, TI 9900)

--Chuck



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