I have the PC85 Microbee from the last post working now. Thanks to Ernest, who persevered in his assistance and identified a mistake in the ROM order, I was finally able to get a proper booting PC85B system. This allows double sized (16K – AKA 27128) ROMs and I’ve got a couple of additional games installed in “high” ROM spots above existing ROMs.
(The PC85 “core” (or top) board is the same between the A and B variants* so it’s a simple ROM swap to upgrade from one to the other)
From here on out, I’ll probably swap out the ROM that currently contains Viatel, as I have no use for that, and swap it for some additional games.
I am also beginning my research on how to make a clear acrylic case for this unit. I figure a nice transparent case will show off the beautiful innards of this system, and it is beautiful.
For anyone who is upgrading the PC85 from A to B, the ROMs need to go in the following sockets:
| ROM Name | IC Socket N° | Lower ROM PAK | Upper ROM PAK |
| ROM E | IC 25 | PAK1 (Help) | PAK9 (Free) |
| ROM F | IC 24 | PAK2 (Spreadsheet) | Reserved |
| ROM G | IC 23 | PAK3 (Graphics) | Reserved |
| ROM H | IC 22 | PAK4 (Viatel) | PAK12 (Free) |
| ROM I | IC 27 | PAK5 (Shell/Menu) | PAK13 (Free) |
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