TSU Meeting MONDAY — February 3, 2025

David, Adam Trionfo, Jeff Burrell, Carl Miles, Tim Swenson, John, Joe, Larry, Christian

Jeff Burrell demonstrated his FPGA-based multi-core board (informally the "2068E"): a ~20,000-gate FPGA with 1 MB static RAM, stereo DAC, two Picos (one for SD card, one for USB keyboard), two joystick inputs, and VGA output. From an SD-card menu it boots different cores; the Spectrum core (derived from MiSTer) works, and the 2068 core is in progress with memory mapping out to the static RAM. He showed a Python front panel that talks to the SD-card Pico over USB serial for file transfer, wrote the menu code in both assembly and C using z88dk, and said he's about two weeks from shipping to beta testers once a flaky UART is sorted out.

David gave a TS-Pico update: the next release needs three steps to apply — a UF2 firmware image dragged onto the Pico, a SD-card-resident set of MicroPython files copied in via an upgrade command, and finally a ROM update flashed in place from the 2068 itself (Ricardo found a way to do this without swapping the flash chip). Adam offered to help record an install video. Adam also reported testing Hi-Rez Hero on real NTSC hardware: it ran, but showed "bright black" attributes the program is documented as avoiding, and asked others with FPGA/Pico video boards to compare.

Carl Miles walked through where his ZX81/TS1000 cartridge ecosystem stands. The 1510-clone interface and 4-game cartridge are stable; his larger 32-program cartridge uses dual 7-segment hex displays driven by a modern BCD-to-hex-seven-segment GAL and is now loaded with 31 Ryan-Gray-ROMified programs (Ryan's p-file-to-ROM utility, with Kevin's Windows binaries, made that possible). A separate ROM-replacement cartridge runs 8K or 16K ROM images, including the Sponzi Spectrum-on-ZX81 ROM and a Timex demonstrator/Memotech/German assembler ROMs; Sponzi inexplicably works on Adam's unmodified TS1000 even though it should require the WRX hi-res mod. Carl is considering a next-rev interface board that bundles 16K RAM (eliminating RAM-pack wobble) and a programmable joystick port — prompted by Larry asking how to play Rocket Man without finger gymnastics.

Other items: the Albuquerque trio (Adam, Carl, Ryan) met in person Saturday and hand-disassembled the TS1500/TS1000 ROMs using Ray Kingsley's Hot Z; Carl gave background on Kingsley (Santa Fe, very private) and Art Colgate's S-Tech Automation work using 2068s to run a 3-axis milling machine. David previewed his upcoming compilation "Machine Language Programming for the Timex Sinclair 2068," a curated set of 80s/90s newsletter and book articles on 2068-specific Z80 topics (hi-res modes, IM2 interrupts, 64/80-column). Tim Swenson reported the ZX-Zine has shipped to all known requesters (6 to Europe) and offered six A&J Microdrive wafers plus a TimeWorks plastic console to a good home. VCF Midwest planning was deferred to the upcoming Sunday meeting; David is still trying to reach Hi-Rez Hero's author, Sue Mahoney, and Partial Pascal author Michael Ambling for guest appearances.

Highlights

Jeff Burrell demoed his FPGA/Pico multi-core board running a Spectrum core from SD card, with a 2068 core in progress
TS-Pico next update is a three-step process (UF2 firmware, SD-card files, in-place ROM flash) — Adam to help with an install video
Carl Miles's 32-program ZX81 cartridge is up to 31 ROMified titles via Ryan Gray's p-file-to-ROM tool
Sponzi (Spectrum ROM on ZX81) runs from Carl's ROM-replacement cartridge — and inexplicably works on Adam's unmodified TS1000
David previewed an upcoming "Machine Language Programming for the TS2068" article compilation covering 2068-specific Z80 topics

Projects discussed: FPGA "Advanced 2068" · TS-Pico · TS1510 Cartridge Interface Clone Topics: Cartridges, EPROM & dumping · Hardware projects & new boards · TS1000 / ZX81 / TS1500 · Pico / modern interfaces (UnoDos, etc.) · Machine code, Z80 & assemblers · TS2068 / TC2068

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