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TSU Meeting SUNDAY — June 22, 2025

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David, Adam, Tim, Ryan, Paul, Jeff, Phil

Tim opened with a recap of a QL-focused Zoom meeting that morning hosted by Martin Hill, which centered on the Sinclair (Interface 1) network — a simple UART-driven protocol that daisy-chains up to 63 devices and is being extended to run over Ethernet/IP, with cooperation from the Spectrum Next team. Tim's suggestion: anyone designing new TS2068 hardware should include the Interface 1 network ports so Spectrums, QLs and 2068s can physically network together. Tim also confirmed that the next issue of ZXZine is essentially written (with one article from an outside contributor) and ready for layout; it is Creative Commons and people are welcome to mirror it or take it to print-on-demand services like Lulu.

David described prototyping a Raspberry Pi Pico W board that emulates the 8251 UART inside the Timex 2050 modem. Working with Claude, he uploaded the 8251 data sheet, generated firmware, and produced schematics translated into EasyEDA — PCBs were due Monday. The board would plug into the 2068 expansion slot and look like a 2050 modem to existing terminal software, but accept Hayes-style AT commands over WiFi, and could conceivably be extended later to carry Sinclair (Interface 1) traffic over WiFi. The group also discussed Jeff Burrell's Pico Video card and its ULA Plus mode, what spare CPU might remain on the second Pico core to do software anti-aliasing, and Andy Dansby's blog posts walking through the Bresenham line-drawing algorithm — first in BASIC, now being rewritten in Z80 assembly.

A long Forth thread covered Jeff's Jupiter Ace emulator cartridge (paired with his Badago keyboard project, where he wants to add Forth words for joystick I/O, sound and video modes), and a tour of TS/Sinclair Forth implementations: Treeforth (formerly Plural Forth, with its famously thick manual on archive.org), Hog Wild Forth (Paul still has the manual), Ava Soft Forth, Quill, fig-Forth, and RPNZL — which the group settled is short for "reverse Polish notation," not Rapunzel. Paul also asked about the recent list thread on running Fuzix (Alan Cox's Linux-like OS for 8-bit CPUs) on the 2068; the consensus was that it can target a Z80 but needs extra hardware and nobody has actually done it on a 2068. They also reviewed the second Spectrum Next Kickstarter — forced to switch FPGAs after Xilinx parts became unobtainium — with a QL core started in December 2024 and a Commodore 64 core likely.

The planned walkthrough of the TS1000 manual got a partial treatment: Ryan led the group to Appendix C (the BASIC-dialect-differences appendix — no READ/DATA, no user-defined functions, and the well-known trick of overloading VAL) and chapter 25's famously thin two-page "Using Machine Code" section, which mostly tells you to go buy other books. A tangent followed on foreign-language Sinclair material: a French ZX81 manual printed in Paris in 1984, German Chip-Verlag compilations of best ZX Spectrum/ZX81 programs (with a tutorial for adding German characters to Tasword 2), and Portuguese Timex Sinclair manuals. Word-processing nostalgia rounded out the meeting — Tasword 2, the Timex 2040 printer at 64 columns, parallel-printer interfaces via Larken/Oliger expansion boards, WordPerfect's function-key codes — along with the open question of whether anything from the CompuServe Sinclair SIG was ever systematically archived (the Tandy Model 100 community managed it; the Sinclair side apparently did not).

Highlights

  • David has Pico W → 2050-modem-emulator PCBs arriving Monday — designed with AI help, will present as a 2050 modem but take Hayes AT commands over WiFi.
  • Tim recapped Martin Hill's QL Zoom meeting on the Sinclair (Interface 1) network and pitched including those ports in any new TS2068 hardware.
  • Next ZXZine is essentially written; Tim is about to start layout.
  • Andy Dansby's Bresenham line-drawing work — BASIC version posted, Z80 assembly version in progress.
  • Spectrum Next's second Kickstarter has a QL core in development (since Dec 2024) and a likely Commodore 64 core.

Projects discussed: TS-Pico Topics: Modems, serial & RS-232 · Pico / modern interfaces (UnoDos, etc.) · Newsletters & documentation · BASIC programming · TS1000 / ZX81 / TS1500 · Machine code, Z80 & assemblers

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