When you had been round for the early days of the non-public laptop revolution, you’ll little doubt recall the thrill each time IBM introduced a brand new model of its beige containers. For lots of us, the thrill was purely vicarious, for regardless of the “private” moniker, mere mortals may hardly ever afford a branded IBM machine. However it was nonetheless cool to maintain monitor of the newest releases, and dream of the times when low cost clones would make it attainable to play.
[Anders Nielsen]’s latest discover of an unique IBM Mannequin 5160 motherboard form of echoes that long-ago pleasure, however differently. This board, from a PC XT in-built 1984, was in unknown situation upon arrival, so [Anders] set a couple of cautious course of to attempt to deliver the board again to life. A fast visible inspection leaves one with a way of each how a lot issues have modified, and the way a lot they’ve stayed the identical. Except for the massive 40-pin DIP 8088 CPU and the BIOS ROMs, the board is nearly utterly populated with discrete logic chips, however on the similar time, the essential footprint of a motherboard has modified little or no.
The bring-up course of within the video under consists of checks of all the ability rails for shorts, which ended up being a great name — drat these tantalums. After fixing that problem, [Anders] had a little bit of bother getting the board to POST, and ultimately resorted to dumping the BIOS ROMs and inspecting the contents. One of many chips had picked up a case of the scramblies sooner or later, which was simple sufficient to repair thanks to pictures of the 5160 ROMs accessible on-line. We thought the trick of utilizing a 64k ROM and simply writing the BIOS picture twice was fairly intelligent.
Ultimately, the board got here up, though with out video or keyboard — that’s for an additional day. Can’t discover your individual PC XT motherboard to play with? Then perhaps you may simply construct one.