Retro Motorola mini-6802 system - lockdown2, 2020 скачать в хорошем качестве

Retro Motorola mini-6802 system - lockdown2, 2020

Another 'lockdown 2020' Retro-Computing project :-) Back around 1980 I worked in BT's Measurement & Analysis Centre, which was a GEC2050 computer that made test-calls and collated results to improve the telephone service. Part of this equipment was a TRT302 printer In each telephone exchange. This contained a 6802 microprocessor board, which we robbed from any faulty printers. I was a Z80 user and this was my first use of a 6800, but I hand-wrote a monitor for it and me & pal Steve made development systems from these boards. 40+ years on, I still have that original board, and the hand-scribbled monitor listing, but the board isnt very reliable, in fact its forever breaking and I thought I'd make a new reproduction using the same hardware and the same monitor program, exactly as it was back in the day. The monitor ('bug') has commands to display memory, modify memory, goto program, a serial loader for 'S' records, breakpoint & register display, ram-vectored interrupt handling etc... quite complex for a hand-coded project in 1980. The Repro is much smaller and neater but works exactly like the old one. Fortunately I found a PCB on Seeed which was exactly what I had in mind - I dont know who designed it but thank you :-) EDIT: the board was designed by San Bergmans (NL) Thanks San! Further edit: I've since been told its not San's board, but Bart someone? I dont know, we'll have to settle for an anonymous credit :-) I found a free 6800 assembler online (A68) which is superb, really easy to use, and I've transferred all my old hand-written code into a proper source file. The noughts-&-crosses game is embarrassingly simple by todays software standards, but its typical of hand-coded, amateur efforts back in the day - of course, its unbeatable, it hasn't lost a game in 40 years! Getting a micro to play a tune, or to calculate a square root or prime numbers was an achievement then, at the time this was all fascinating new territory for the electronics hobbyist. To get the best out of these old systems a thorough understanding and familiarity is essential, and these of necessity were common skills amongst many thousands of electronics hobbyists. Conversely, its said that today, fewer than 100 people in the world fully understand whats inside an ARM Cortex processor. How things have changed! Cheers Phil PS Having pondered on it, I think the 1978 guess was too early. Maybe early 80's? Edit: The monitor has been extended quite a bit since the video. In addition to the commands shown, it can calculate relative jump offsets, fill memory, it has breakpoints and interrupt handling, BIOS-style jump tables, and it now loads serial files in Motorola S record format rather than Intel. Its a very capable monitor, with many more features than Motorola's Mikbug! PPS "Stalemate" is what I should have said! (I'm no chess player...)