Timex Sinclair User Group Meeting with European Friends — October 16, 2022
David Anderson, Thomas Aaron, James March, Stuart, Adam Trionfo, Johnny Red, Jeffrey Kuhlmann, Tim Horner, Ingo, Joe, Willie, Chris
The Sunday-afternoon "European-friendly" session opened with introductions from two newcomers. Thomas Aaron described a hobby project to write a Sinclair BASIC interpreter in Common Lisp (using a Python interop layer and Tkinter to simulate the screen). James March — author of the 1980s Timex Sinclair User's Encyclopedia, originally an East Bay Zilog Users Group / Timelines contributor — surfaced with two attic boxes of TS hardware, books, tapes, a 64K RAM board and a Memotech calculator pack, and offered signed copies of his book; David offered to scan one for the archive, and Stuart walked him through the eBay route for the rest.
A long, demo-driven segment with Johnny Red (João, Portugal) covered the Timex Portugal FDD disk system. Johnny ran FUSE with FDD emulation, showed the TOS on-disk layout (boot tracks 0–3, directory track, then data; 40- and undocumented-80-track formats), the per-file header sizes (7 bytes for BASIC programs, 5 for code/arrays), a Polish Bajtek-magazine disk-doctor and sector-editor, CP/M booting with the Timex Terminal 3000 (a keyboard-shaped Z80 computer that supplies the video for the otherwise-video-less FDD), and the rare Polish Unipolbrit 2086 variant. He pointed to a heavily-annotated Polish FDD/TOS technical writeup he has translated into English, and to the move of his long-running site into the Lord ZX Museum (whose second anniversary is next weekend, with a video of a meeting of ~70 ex-Timex-Portugal staff now available with English subtitles). The information directly unblocks David's plan to image a stack of Timex-Portugal disks Joe will be extracting.
The technical thread of the meeting was DOCK-cartridge tooling. Adam reported that 'EightyOne' (per a screenshot from Jeff) supports Z80 single-stepping — what he needs to trace the Qbert code he has been disassembling — and that his new Backbit cart with the 2068 adapter works once the resistor pack is shifted, though it's power-flaky until he tries Carl Miles's replacement supply. Jeffrey Kuhlmann is scripting cartridge-image construction in PowerShell: build an empty DOCK, stamp the TS2068 AROS header, drop in a BASIC program via ZMakeBase, set autostart, and test in FUSE; he is relearning Z80 in OshonSoft's Z80 IDE (single-step, variable-speed sim, virtual I/O) and asked about the RAM-reserve bytes in the 8-byte header and the 9-byte DOCK leader that has to be stripped before EPROM burning. David pointed him at the Third-Party Software Guide and his own commented ROM source.
Hardware projects: Stuart introduced a printer-bridge project he is co-developing with Tim Horner (New Zealand) — a TS2040/Alphacom interface as an Arduino Uno shield with a Qwiic connector for I²C sensors, GPL-style open hardware/firmware on GitHub, designed both to drive Sinclair printers from modern micros and (next iteration) to bridge a Timex to an Arduino as a clean sensor/SPI/I²C front-end; Stuart will mail boards to anyone who wants one once the second-rev prototype is verified. Ingo built a four-port Z80-PIO parallel-I/O board to help debug ZX81 ROM keyboard routines (toward a keyboard buffer). Side discussion covered tactile keyboards (Ginger Electronics; David Stevenson's ZX81 keyboard-adventure full-size cherry-switch design with USB-HID via an Arduino Nano), ZX81 16K/32K internal RAM mods, switching-regulator swaps, and a clean drop-in 32K SMD upgrade board Joe linked. Next meeting: Monday Nov 7, 9 p.m. Eastern; Jeff Burrell's project and more DOCK-format work to follow, plus a possible separate "nerdier" session on machine-code tooling.
Highlights
- Johnny Red demoed the Timex Portugal FDD3000 in FUSE — TOS disk layout, file-header sizes, a Polish sector editor / disk doctor, and CP/M via the Terminal 3000
- James March (author of the 1980s Timex Sinclair User's Encyclopedia) surfaced with two attic boxes of hardware and books; David will scan a copy for the archive
- Jeffrey Kuhlmann is scripting DOCK-cartridge assembly in PowerShell (TS2068 AROS header + ZMakeBase + autostart) and using OshonSoft Z80 IDE to relearn Z80
- Stuart announced a TS2040/Alphacom printer-bridge Arduino shield co-developed with Tim Horner (NZ) — open hardware, free boards once the rev-2 prototype lands
- EightyOne emulator confirmed to support Z80 single-stepping — what Adam needs to trace his Qbert disassembly
Topics: Disk & floppy systems (Larken, AERCO, Oliger) · Cartridges, EPROM & dumping · Machine code, Z80 & assemblers · Printers & plotters · Hardware projects & new boards · Timex Computer (European: TC2048/3256)
Summary generated from the meeting recording; the full transcript is kept in the group's private archive.