Timex Sinclair User Group Meeting — March 7, 2022
David Anderson, Greg, Adam Trionfo, Jeff Burrell, Tim Swenson, Carl Miles, Jamie Macbeth, Stewart Newfeld, Willie Jones, Rich, RW Johnson
Greg opened with a Wordle clone he wrote for the ZX81 using ZMakeBase. He packed ~2,205 five-letter words into a single ~11K REM statement (uneditable on real hardware), used a binary search for word verification, and had to patch ZMakeBase to handle a line buffer larger than ~2K — a change he plans to push back upstream. He demonstrated it running on emulator and on real hardware via ZXpand (and as a WAV load), and Adam admired the period-correct printed manual Greg made.
David reported on the Timex 1000 demonstrator ROM that Jimmy Ipok had identified — the unit Timex built for Kmart kiosks and that E. Arthur Brown later sold for $20. With help from Sinclair ZX World, the group worked out that it loads at $2000 (in the 8K gap above ROM) rather than as a normal tape file. David also discussed Tim Swenson's ZX-text-to-P transpiler — Adam has been testing programs through it; both hit a substring/keyword false-match (e.g. "freeze" matching FREE) and fixed it by turning off the case-insensitive flag.
Jeff Burrell talked through his work porting UnoDos (essentially a disassembled, freely-distributable ESX-DOS variant) to run natively on the TS2068. His FPGA 2068 board can now boot as a Spectrum running UnoDos or ESX-DOS, and he's relabeling absolute addresses in the source so it can be recompiled for the 2068. The tricky part is that UnoDos uses XROM load/save tape routines whose addresses collide with the NMI vector area, which would also require modifying the DivMMC's CPLD to snoop the right addresses on a 2068.
Carl walked Jamie Macbeth through diagnosing a TS2068 that boots to horizontal black-and-white bars — likely bad RAM (chips that get burning-hot, possible shorted address/data lines), with concrete probing and desolder steps and a pointer to the Sams Photofacts for the 2068. Carl also showed off cartridge PCBs he ordered for the TS1000/ZX81 (aiming at 3D Monster Maze) and asked about the TS1500 cartridge header format. A long thread on tape archiving covered: capture as WAV/FLAC (never MP3), Audacity / Adobe Audition, hum and high-pass filtering, azimuth adjustment, make-TZX, why hand-fixing waveforms is a last resort, and an Australian touchscreen multi-format tape player Carl is on the waiting list for. Willie Jones unveiled a wooden silver-painted DMU-style expansion box he built around his original Oliger DOS + floppy controller cards, with a matching painted Alphacom — and asked the group how to get disk contents into TAP/TZX so he can share type-ins. Tim Swenson closed with stories of running MTD Software in 82–83 and using a TS1000 + Memotech Centronics + Epson RX80 to print mailing-label newspaper receipts on his paper route.
Highlights
- Greg demoed a ZX81 Wordle clone (~2,205-word dictionary in a single 11K REM) built with a patched ZMakeBase
- Sinclair ZX World helped decode the Timex 1000 Kmart-kiosk demonstrator ROM — loads at $2000, not as a normal tape file
- Jeff Burrell is porting UnoDos to run natively on the TS2068, using his FPGA board to validate UnoDos/ESX-DOS first
- Carl gave Jamie a step-by-step RAM-fault diagnosis for a 2068 booting to horizontal bars, and showed new ZX81/TS1000 cartridge PCBs aimed at 3D Monster Maze
- Willie Jones built a wooden silver-painted expansion box housing his original Oliger DOS + floppy controller and a matching painted Alphacom
Projects discussed: UnoDos · FPGA "Advanced 2068" · Library Tape Archiving Process · TS1510 Cartridge Interface Clone Topics: TS1000 / ZX81 / TS1500 · BASIC programming · Tape & library archiving (TAP/TZX) · Tape, cassette & loading · Pico / modern interfaces (UnoDos, etc.) · Repair & restoration
Summary generated from the meeting recording; the full transcript is kept in the group's private archive.