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I’d got a Gotek floppy drive emulator running the FlashFloppy firmware but had not yet been able to get it working and suspected it was something to do with the pin34 setting. Looking at the schematic for the GM829 board, shows that this is jumpered to support a fourth drive rather than the RDY signal.

Looking at the board, these were jumpered with wire links and the PCB tracks were also jumpered the same.

The wire links were removed, the holes cleaned up and the PCB tracks were cut.

I used some 3 way 0.1″/2.54mm header pins with the centre pin removed to make pins for new jumpers.

Some re-usable links were made from 3-way and 4-way Dupont header shells. The 3-way to restore the original configuration. The 4-way is to link pins A to D.

After these modifications were made I connected the Gotek, set the jumpers to Drive 0 and powered on. After selecting the first image it booted. Now to explore other images and get an image working with this system.

After 40+ years, the disk drives need a bit of maintenance. Fisr they were removed from their mounting frame, each was identified as being the same model which makes swapping them around a lot easier.

I’ve not been able to find my old disk head cleaner so using cotton buts and IPA were used instead. Drive A appears quite dirty, so was probably the cause of the the disk read errors. I assumed that drive C would have been the least used so was swapped with drive A. The drive selection links needed to be swapped too.

The drives were replaced, machine reassembled and tested. No disk read errors were seen during initial testing.

I took the QM2000 and many other machines to a local retro computer event. One of the visitors had brought some Gemini floppy disks to try. Thanks John, much appreciated. The original monitor was connected and powered up nicely.

The result is thaat it was able to boot to CP/M 2.2. The next stage is to create a system disk for this that can access all three drives.

I’m looking at getting this QM2000 up and running and as a software task, dissasembly of the ROMs is the fist stage. Looking around, the ROM images don’t appear to exist on-line due to the QM2000 being a rare beast. The EPROMs on the GM813 Z80 board and the GM812 Intelligent Video Controller were dumped. Using Claude-Code to perform analysis on the disassembled code, it was able to produce a comprehensive description when combined with the available hardware and software documentation available for the boards. Existing versions of the monitor code were compared to verify the disassembly and analysis was correct.

The monitor ROM for the GM813 was found to be an early version of the SIMON Monitor specifically coded to use the GM829 Disk controller.

The output from the disassembly is available in my QM2000 Github repository.

It needed a little bit of dismantling to get to the power supply and upon opening it up, first impression was that it looked ok. On closer inspection a number of the capacitors were in need of replacement. New capacitors are on order.

The main power switch was replaced and a new VDU socket was added as I didn’t have a plug for the original.

I recently acquired a Quantum Computers QM2000 at a local auction. Having never seen one before I was interested to see what it was like. It was listed as not working due to having failed a PAT test and therefore the power leads were not included. One of the few sites I found showing the computer in magazine advert from 1983 They QM2000 is based on the Nascom-2 bus with cards made by and sold under the Gemini name. There is some limited information on the QM2000, but more information and schematics for the Gemini cards. At this time it has not been powered up as it would need the mains electrical sockets replacing and the Power supply capacitors replacing.

It has a selection of connectors on the rear that connect to various peripherals.

Inside of the QM2000.

The main boards can be removed.