TSU Meeting MONDAY — March 2, 2026
David Anderson, Adam Trionfo, Ingo, Paul Anderson, Ryan Gray, Ricardo Calcagno, Richard Jelen, Carl Miles, Gustavo, Tim Swenson
Ingo opened with a status update on the KiloZ keyboard: a new black PCB, glass-fiber ABS bezel, and — most importantly — UV-printed key caps from 3D Key Cap that replace the old water-transfer decals. He and 3D Key Cap are preparing a Kickstarter (target ~$50 CAD per set, $1,000 goal) to run in April, and they're considering a fuller kit later (key caps + bezel + switches, or even a complete KiloZ kit on Carl's new motherboard). David offered practical Kickstarter advice (set up the page early for the 'notify me' list; promote heavily for ~60 days before launch). Gustavo suggested an expanded six-bits-per-row matrix to add numeric keypad, escape, control, etc. as a future variant, and the group noted the same template/approach could be reused for a TS2068 mechanical keyboard (Hayden has been modeling a case).
David demoed PastaPas, a Windows-hosted Pascal cross-compiler for Z80 (CP/M, Spectrum 48K, and Spectrum Next) that David Sully had been trying to install — its RTL is in Pascal with a small CX-ROM assembly file (RST 16 for character out, channel 2 open at init), which Gustavo pointed out should be straightforward to retarget for the TS2068 by remapping the ROM call to $1230. A second Pascal mention: HiSoft Pascal on Spectrum/2068. Adam then walked through his conversion of the QuickBasic game 'Skirmish' to TS2068 BASIC, including the workaround for Sinclair BASIC's Procrustean fixed-length character arrays — he used Claude (4.6) to help port it, substituting a scratch variable when player names had to be interpolated into sentences.
That led into a longer AI-tools discussion. The group acknowledged the copyright/training issues (the recent Anthropic settlement only covered ISBN'd works), shared a YouTube video Ingo found on LLM hallucinations, and traded notes on shouting 'representative' at AI drive-thrus. David then walked through two substantive AI-assisted projects: a WordPress plugin he had Claude write to fix breadcrumb parent-relationships for custom post types on the Timex/Sinclair website, and — the meat of it — about 15 hours of Claude Code work on the TS-Pico. Paul Anderson had been hitting an intermittent 'D' BREAK-style error on mount/load that reproduced on some 2068s but not others. After hours of failed in-place fixes, David switched strategy: take the known-good production firmware and have Claude port the new load commands into it, adding extensive debug logging routed through Thonny so he could paste the trace back into Claude. That worked. He then had Claude bring the rest of the new code across, write an API document, and diff Ryan's and Ricardo's branches. Gustavo and the group discussed converting a TS-Pico board into a bus-trace/debug board (only ~11 lines needed — data + RD/WR + IO + A0 — no address bus, no extra RAM/ROM).
Richard Jelen asked how to use a 32K expansion on a TS1000/ZX81. David shared the Memotech 32K manual: POKE 16389,128 sets RAMTOP for 32K. Rich's follow-up — the difference between a standard 32K add-on (which leaves a 16K hole because the upper bank lives at 49152–65535) and an internal upgrade on the VLA81 (which gives one contiguous 16384–49151 block) — pulled Carl into a deep dive on why the upper 16K is hard: the ULA needs to see a ROM mirror up there during video refresh, the CPU has to execute NOPs while the ULA reads display data, and any RAM up there has to be gated by an M1-not circuit. Carl described how his enhanced TS1000 ('1068') prototype handles this with a 512K RAM chip giving eight 64K banks, battery-backed lower 8K for custom ROM and UDG routines, and shadow-ROM swapping. Rich also detailed a CMOS-based composite-video back-porch circuit for the 2C184 ULA that he found works far better than the 555-timer modules sold online — David asked him to draw it up in iVix and post the schematic. Tim Swenson briefly explained RPM as a native Z80 CP/M clone (vs. the 8080-on-Z80 original) used on the AERCO disk system. Next meeting: Sunday March 15 (the Ides of March).
Highlights
- Ingo unveils UV-printed KiloZ key caps; Kickstarter targeting April launch (~$50 CAD/set).
- Adam ports the QuickBasic game 'Skirmish' to TS2068 BASIC with Claude's help, working around fixed-length string arrays.
- David spends ~15 hours using Claude Code to fix an intermittent TS-Pico mount/load bug Paul Anderson hit, by porting new commands into the known-good firmware.
- Carl walks through the M1-not / shadow-ROM / 512K bank-switched RAM design of his enhanced TS1000 ('1068') prototype.
- Richard Jelen shares POKE 16389,128 for 32K RAMTOP and a CMOS-based composite back-porch circuit that outperforms the 555-timer modules sold online.
Projects discussed: TS-Pico · "1068" — Enhanced TS1000 Topics: TS1000 / ZX81 / TS1500 · Hardware projects & new boards · Pico / modern interfaces (UnoDos, etc.) · Video upgrades (composite, RGB, HDMI) · BASIC programming · CP/M
Summary generated from the meeting recording; the full transcript is kept in the group's private archive.