These look like they're from 486 era file server hardware. On Mon, Jun 24, 2019 at 11:16 AM Kyle Owen via cctalk <cctalk at classiccmp.org> wrote:

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: