A friend recently introduced me to the world of Retrocomputing. Specifically the work of Sergey Kiselev. Sergey has evidently dedicated many years to the creation of completely open-source designs paying homage to early computers such as the IBM PC-XT.
One such system is Sergey’s Micro 8088 processor board paired with Sergey’s ISA 8-bit backplane. A friend of mine was interested in building a system around both of these boards. Being an open-source design, the PCBs must be ordered by engaging with a PCB fabrication house. The minimum PCB order was in units of five, so I was offered one of each board to maybe build a retro system of my own. Of course I said yes. But what would I do with a system of my own?
As an aside, I had collected a number of old computer boards from my childhood. It was quite normal back then to throw away a whole computer by leaving it outside your house during “hard rubbish collection”. As a child, I would ride my bike around the neighbourhood and salvage different machines that were left outside. I collected boards from many different machines: 286, 386, and 486 motherboards, and a handful of different graphics cards.
I ultimately decided: I want to build a system to play retro games from my childhood, possibly using parts I saved from when I was a child.
Looking though my stash of parts from two decades ago, I found something of extreme interest; an original IBM CGA graphics card:
This card would be a perfect complement to an early 8088 computer system.
The card is marked “1501981APS” in white text just above the HD6845 CRT controller chip. To the right is what appears to be a white ink stamp of the number “6278604”. Above is what appears to be a white ink stamp of the number “000”.
Inspecting the board, it became quickly apparent that I had done something very stupid in my youth; around a dozen traces on the top and bottom side of the board had been cut and pulled off. That must have been entertaining back in the day, but now in retrospect I want to slap myself:
Irritated by my own senseless destruction, two thoughts bounced around my head.
The first thought; I want to repair the board I had damaged and attempt to get it working with Sergey’s Micro 8088.
The second thought; maybe I can “apologise” to the board and atone for some of my guilt at damaging it by designing a “clone” in KiCAD as a sort of homage, and then open source the design for future generations to enjoy and learn from.
Will either of these ideas work? Will I give up halfway though? Please join me through what I presume will be a multi-part series as I adventure with Retrocomputing.