Annals of OS and network history

From: Jack Peacock <peacock_at_simconv.com>
Date: Tue Mar 10 14:57:21 1998

>> and I am interested in something that had a processor that
>> interacted w/the user and a separate one to do the
processing
>> (ie a real-time system capable of doing all that a normal
one can)


The earliest machine I know of that did this on a large scale
was the 6000 series from CDC, starting with the CDC 6600 in late
60's, designed by Seymour Cray. The main CPU was a superscalar
60 bit processor with no I/O instructions or ports, just memory.
All I/O was handled by PPUs (peripheral processor units), which
if I recall were 24 bit CPUs, (very hazy recall here) using an
older CDC 924 type instruction set. The PPUs had direct memory
channels into the main CPU. The operating system posted
messages to the PPUs for I/O requests. The PPUs were not user
programmable, but could be programmed at the system programmer
level.

More recently, Intel designed the 8089 I/O co-processor as part
of the 8086 family. It had an instruction set optimized for I/O
functions. I vaguely recall someone made an S-100 board with an
8089 on it (was it Godbout?) but it never caught on.
            Jack Peacock
Received on Tue Mar 10 1998 - 14:57:21 GMT