May 2021

Digital Necromancy

As mentioned before, back in the late eighties I built a 68000-based computer. Last time I messed with it was probably in 1991, 30 years or so ago.

Well, it still lives. It runs a hacked version of MVME101bug, and I also have Gordon Brandly’s Tiny Basic along with a bit of code to copy it to RAM at 0x002000 and run it there.

But I have given up trying to hack MVME101bug any further. These days I have the source for the Motorola MC68000 ECB TUTOR monitor, and I know how to compile it, and it’s basically the same thing*, so that’s where I’m going next.

* In addition to the TUTORNEW commands, MVME101Bug has BI (initialise block of memory), BD, BH, BO (bootstrap from floppy), and IOP, IOT (disk I/O). It takes up aroung 22k of EPROM space, while TUTOR had to fit in 16k. I will worry about that when I get there.