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TSU Meeting SUNDAY — August 23, 2026

David, Jon Becker, Ryan, Adam, Stuart, Gustavo, Joe

John opened with an update on his AI-assisted (mostly Codex) work for the TS2068. He has done several cartridge conversions and ported the Spectrum game Elite to a 64K TS2068 cartridge with a title screen. The AI drove the Fuse debugger through scripts to track down crashes on its own. John also built a delta-based video codec that turns short clips into extended color mode (ECM) animations, packed into a TAP or a 64K cartridge. It bank-switches 8K dock chunks and uses a "FIFO packing" scheme to fill about 56K. Its dithering borrows from the Retro Pixel Converter. The group asked how the dock chunks map into memory, and John will post a follow-up explanation. Two more of John's projects are in progress. One is a straight Z80 port of the arcade game Berserk to ECM, with speech samples streamed through the AY chip's volume register. The other is a small, cheap, USB-programmable TS2068 cartridge based on the open PicoROM design, now headed to fab. David noted that the TS-Pico can map a 64K image from flash or RAM to the dock, but it conflicts with physical cartridges.

David demoed Space Trader, a Traveller-style trading game written mostly in BASIC with Claude's help, using John's ECM work for per-system artwork. He also described teaching Claude how to pull machine code out of ZX81 REM statements. The group looked at the original Timex catalog: cartridges cost roughly twice the cassette price (e.g. Androids $20 on tape vs $35 on cartridge). David also shared a 1980 Syntax article on Dave Thornburg's "Presto Digitizer" for the ZX80, which connects to the later Koala Pad.

Stuart gave a tour of his first working OpenSpand build. OpenSpand is an open-source, Pico 2-based ZXpand replacement for the TS1000 with an SD card, composite video, RTC and digital audio. He covered the stacked-header construction, RTC modules with mismatched pin spacing, heat-set inserts for the case, and an open question about bus loading with no buffer chips. The group also looked at Don Crawford and David Spinette's "1526" variant, whose 3D-printed case is styled like the TS1510 and has a microSD slot hidden in a cartridge plus a joystick port. Gustavo pointed out how closely that case resembles Timex Portugal's FDD3 interface.

Announcements: the group will have tables at VCF Midwest. Expected exhibits include Carl's TS1510 clone and his "1068" enhanced TS1000, Joe's speech synthesizer work, and John's ECM slideshow, and Stuart hopes to bring about 10 OpenSpand units. The next meeting is Labor Day Monday at 9pm Eastern. David proposed inviting original Timex staff to the 127th meeting in February and holding a 128th-meeting celebration of community projects. Stuart suggested future sessions where members demo how they use AI tools. Eduardo's Oliger disk emulation in Fuse was noted as a big recent milestone. Ryan closed by demoing his BASIC palette editor for ULA+ on Jeff Burrell's Pico video card, which handles 8-bit GRB palette quantization, palette-group limits and gamma tuning. The group agreed he should give a fuller demo at a later meeting.

Highlights

  • John ported Spectrum Elite to a 64K TS2068 cartridge with AI help and built an ECM delta video codec
  • John's PicoROM-based USB-programmable TS2068 cartridge is going to fab; his Berserk ECM port with AY speech is in progress
  • Stuart completed his first OpenSpand build for the TS1000; the 1526 cartridge-style variant was also reviewed
  • David demoed Space Trader, an ECM Traveller-style trading game built with Claude
  • Ryan demoed a ULA+ palette editor for the Pico video card; plans set for VCF Midwest and a 127th/128th meeting celebration

Projects discussed: Openspand · TS-Pico · Retro pixel converter · TS1510 Cartridge Interface Clone · "1068" — Enhanced TS1000 Topics: Cartridges, EPROM & dumping · Pico / modern interfaces (UnoDos, etc.) · TS1000 / ZX81 / TS1500 · Video upgrades (composite, RGB, HDMI) · Games · User group meetings & events

Summary generated from the meeting recording; the full transcript is kept in the group's private archive.