LM Ericsson USE 6800
Introduction
In the early 1980's, the Electronics Division of the Physics Department of Umeå University, that later became the Department of Applied Physics and Electronics, gave LM Ericssons now defunct factory in Östersund the task of developing and building a development system for the Motorola 6800 and 6809 microprocessors. The result was USE 6800 – a modular system built out of, what I believe are, AXE telephone exchange system components, as well as custom ones, built into a military grade-looking cabinet.
It was given to me, among a huge pile of other things, by my old university teacher and friend Håkan Joëlson, that had to downsize his (quite respectable) collection. I believe he used this system to write his thesis project, and he then saved it from ending up in a landfill when more modern systems were brought in. He doesn't know how many was originally built, but it seems unlikely that there are any more left except this one.
The system runs the FLEX (and FLEX09) operating system by TSC, Technical Systems Consultants, an operating system that was first released in 1976, and had its last release in 1985 – just a couple of years after the USE 6800 was made. I had never heard of it before I came across it in the manuals for the USE 6800, but as it was only released for the Motorola 6800 and 6809, and had its last release when I was five years old, that's probably to expect :)
The cards
The computer is built out of discrete cards that are pushed into a backplane. All cards have the same two connectors that plug into the backplane, but so far I'm unsure if all connectors are wired the same, or if they have to sit in a specific slot. The floppy drives are also connected to the backplane with the same two connectors, and at a glance it looked like they were more or less connected straight through with no logic between the floppy and the floppy controller. Investigations will have to be made...
CPU card P/N ROF 137 3204
Apart from the Motorola MC68B00S CPU, there are quite a few other ICs on the card; a Motorola MC68B40S programmable timer module, a [Motorola MC68B50S](Motorola MC6850 Datasheet.pdf) ACIA, two Fujitsu MBM2716 EPROMs, a Thomson EF6821P PIA, an unknown Fujitsu MB472, and a bunch of glue logic. Fun fact: The only card (not counting the simple power distribution card and the peripheral display/keypad) without any bodge wires.
The CPU card (albeit not this one) was sitting in slot 1 of the backplane when I got the machine. We'll see if that's correct, but it seems likely.
CPU card P/N N/A
RAM card P/N ROF 137 3201
IO card P/N ROF 137 3202
Floppy controller P/N ROF 137 3203
Power distribution P/N ROF 137 3299
