6809 CPU Board

[eastonj]

Back in College I bought my first retail computer, a OSI Challenger 2P with 5.25 floppies. I eventually acquired a larger case, 8 slot backplane and gutted the cards out of the 2P into the larger system with some 8" floppy drives. We also eventually got a couple of 4P systems and some other cards. After I married and moved out, the OSI systems languished in my Parents attic as I moved on to other computer systems.

Fast forward to today, my parents are moving out of the house to another place in retirement and I was called to help clean out the place. I figured I'd collect the OSI systems but alas, when I arrived, most of the OSI stuff had already been sent to the local electronics recycling center. I did manage to find some bits and pieces and a few boxes of documentation.

One card of interest is this 6809 CPU board I designed probably in my Junior year when I took a Printed Circuits class. We had to layout a board and etch it for class so I worked up this design to replace the existing 6502 cpu card in my OSI system. As I recall, I adapted a monitor program published in either Byte or Kilobaud magazine for a 6800, recompiling it for the 6809. This OSI version of the monitor program was pretty primitive. In the intervening years I fleshed out the code some more and made 6800, 6809, and 68HC11 versions once I got a real assembler, to use on various single board computers I designed. This OSI version was hand assembled.

[dave]

Welcome!

Very cool.

[Scott Larson]

I made a PC board in my electronics class back then. It was... a guitar amplifier. Not quite the same level as this. I remember we used a huge arc lamp as a UV light source to blast away all the copper leaving the covered parts as traces.