Identifying some boards

[Mike Niswonger]

Originally, System Engineering Laboratories (SEL) out of Fort Lauderdale 
(later bought by Gould (Gould SEL), then NEC and finally spun off as 
Encore) built one of the original 32 bit mini computers (and later 
super-minicomputers) in the 70's -90's.

Popular for large flight simulators and nuclear power plant control, 
they were high performance real-time computers.

The instruction set was designed and implemented in many technologies.  
In the latter days, micro-programmed bit slice architecture enabled the 
company to squeeze the performance of a multi board CPU set down onto a 
single board.

The VERY large connectors seen were the standard backplane, the SELbus.  
The central pins were actually the bus itself, while pins on the end 
were carried through the backplane to create an IO bus where boards 
plugged onto the BACK of the backplane.

The instruction set was nice and easy to code in assembly.  The machines 
I worked with in the early 80s )32/87, 32/8780, 32/9780) were typically 
about 4 times faster than a VAX 11/780 and considerably faster for 
interrupt response in a real-time environment.  The primary OS was 
called MPX-32. though machines with a slightly modified instruction set 
(called PowerNodes - PN9000) ran a Unix variant.

Primary programming languages were FORTRAN and assembly.

This class of machine (minicomputers) of course fell to the side once 
microprocessors picked up speed in the 90s...

The architecture is generally referred to as SEL32 - there is a mostly 
complete SIMH implementation of this architecture that needs some more 
testing and debugging.

Those were fun times.

Mike Niswonger,
crufty old minicomputer and FORTRAN programmer


On 6/24/19 10:16 AM, Kyle Owen via cctalk wrote:
> I picked up these boards many weeks ago, but haven't photographed them
> until recently. Some of them are pretty disgusting, but some of the others
> look alright.
>
> Anyone have any idea what these came out of? Some are labeled Gould, others
> are labeled Encore.
>
> http://imgur.com/a/d9iK9qb
>
> Thanks!
>
> Kyle
>