id5100/DECISIONS.md

id5100 — Decisions

Format: YYYY-MM-DD: <decision> — <why>

• 2026-06-14: Pure-stdlib termios instead of pyserial — system Python is PEP-668 externally-managed; per the escalation-brake rule, --break-system-packages for one dependency is the wrong trade. termios is zero-install and reusable.

• 2026-06-14: Layered as codec (civ.py) / transport (radio.py) / CLI (cli.py) — the codec is pure and unit-testable; web UI / HA-MQTT front ends bolt onto the transport without touching byte plumbing.

• 2026-06-14: TDD the codec against the real probe capture (00 00 30 47 01 ↔ 147.300000 MHz) — gives a hardware-true vector, not a made-up one.

• 2026-06-14: Cable lands on [SP2] (= CI-V), 9600 baud, addr 0x8C — verified live, not assumed.

• 2026-06-14: Web panel = stdlib http.server + single panel.html, no framework — keeps the no-deps promise; the UI is one self-contained file. One shared Radio guarded by a lock (CI-V is half-duplex; concurrent transactions would interleave).

• 2026-06-14: transact() returns as soon as the radio's reply frame parses instead of always burning the full timeout — dropped a full status poll from ~3.6s to ~0.2s, making a ~1 Hz live S-meter poll viable.

• 2026-06-14: Aesthetic = industrial instrument faceplate (amber VFD via DSEG7 font, LED S-meter, illuminated mode buttons) — matches the radio-gear domain and the Sethian dark/orange brand. Verified by headless screenshot.

• 2026-06-14: RepeaterBook integration — local repeaters.json + a proximity-ordered panel "Repeaters" card; tapping a row tunes the radio (freq + duplex + tone) over CI-V. Operating convenience without per-request API calls.

• 2026-06-14: CSV-only data path (dropped the token-gated API client + systemd timer). RepeaterBook's API is now auth-gated (401 auth_missing, manual app-token approval); Seth supplied a CSV proximity export instead, so manual re-ingest is enough (YAGNI).

• 2026-06-14: No lat/long in the CSV → rank by file order (RepeaterBook's own proximity sort) instead of haversine. The export is already nearest-first; geocoding is overkill.

• 2026-06-14: Mixed FM+DSTAR repeaters labeled FM (operable as analog now); pure DSTAR labeled DV (freq/offset only — call routing is set on the head).

• 2026-06-14: Live CI-V verification of repeater commands. Verified on the rig: duplex direction 0x0F (read → 0x10 simplex), repeater tone 0x1B/00, tone-switch 0x16/42. The tone field is 3 bytes on the wire (00 pad + 2-byte BCD, e.g. 00 08 85 = 88.5 Hz) — radio.py adds/strips the pad. A full tune_repeater to a live repeater ACKed every step. Offset amount cmd 0x0D is rejected (NG) by the ID-5100 → removed; the radio applies its configured auto-offset when a duplex direction is selected, so standard (0.6/5 MHz) repeaters work from duplex alone.

Deferred / Rejected

• Full software control-head replica — rejected: the detachable head talks a proprietary, undocumented bus to the main unit; CI-V exposes operating functions only (no menu/LCD mirror). Not worth reverse-engineering.
• pyserial — rejected (see above).
• DV mode set — deferred: 0x17 unverified on this radio; don't ship set_mode('dv') as trusted until confirmed against the manual's CI-V table or the live rig.
• RS-MS1A data-jack protocol (D-STAR DR/callsign/messaging) — out of scope for this CI-V layer; separate effort if wanted.
• RepeaterBook API client + daily systemd refresh — deferred (CSV-only chosen); revive if hands-off refresh is wanted. The token-request form text is in the design spec under docs/superpowers/specs/.
• CI-V offset-amount control — rejected: the ID-5100 NGs cmd 0x0D. Offset amount is a radio-side config (auto-offset); only direction (DUP±) is settable over CI-V.
• Distance/haversine ranking — rejected for the CSV path: the export has no lat/long and is already proximity-sorted, so file order is the rank.