Add-on dossier
A linkable lifecycle record for hardware expansions, app ecosystems, firmware upgrades, cases, radio parts, and post-event badge experiments.
The board's J1 20-pin edge connector lets attendees slot in their own hardware; no pinout for it is published.
Badge context
Hackaday preview by Tom Nardi, October 13, 2026, describing the calculator-style ATmega328P-P badge, its DTMF generator, games, badge linking, edge connector, assembled or kit options, bare-PCB distribution, printable cases, and on-site Zebra ID printers.
Official badge page with the user manual (calculator, tones, secret game codes, serial menu, badge-to-badge link wiring), the full bill of materials, and soldering-station build instructions. The October 19, 2026 revision gives the link wiring as RX on pin 15 and TX on pin 16.
Official STL and 3MF files for single- and multi-colour front cases and a supported back case, with orientation and bridging notes and M3x6 screws; marked © 2026 JawnCon, LLC without an open licence.
Official site for the October 16-18, 2026 conference at Arcadia University's Commons Building. The October 15, 2026 check still read Badge information coming soon! on the homepage. The October 21, 2026 recheck found the MOTD updated on October 17, during the conference: this year's badge has sold out, previous years' badges serve as admission, and Jorj has found and fixed bugs in the badge, with a reprogrammer in the Chillout space and a firmware download. The page still carries the TICKETS ON SALE NOW! link and has no wrap-up.
Intel HEX firmware linked from the official homepage on October 17, 2026 as the fixed badge code that attendees could load themselves or flash with the Chillout-space reprogrammer. 60,396 bytes as text and 21,462 bytes of AVR program data, SHA-256 bc1250a87f4d7acfb1601d1c1cd9c998d7e4c5395213caf2c3fe06fb87d4249d, served with an October 17, 2026 last-modified date. No source or licence accompanies it.
Source trail
Secondary pre-event media source corroborating the ATmega328P-P calculator badge and adding that it comes assembled or as a kit and is distributed as a bare PCB.
Primary official source for the October 16-18, 2026 dates and the Arcadia University Commons Building venue. The October 17, 2026 MOTD, written during the conference, says the badge sold out, accepts previous years' badges as admission, and offers Jorj's firmware fix through the Chillout-space reprogrammer; it is the basis for marking the edition completed. It gives no badge count.
Primary official source for the printable case files and screws; it establishes the case design, not its distribution.
Primary official source for the badge's functions, game codes, serial menu, link protocol and pinout, bill of materials, and kit build process. The October 19, 2026 revision corrects the link pins to 15 (RX) and 16 (TX). It names no designer and publishes no schematic.
Primary official firmware artifact, inspected locally: an AVR image whose strings include the badge menu, boot-text rules, high scores for Vault, Hex Recall, DTMF Recall, and Higher-or-Lower, the keypad-not-found error, and the badge-to-badge link prompts. It documents the fixed firmware, not what each badge shipped with.