Original intent: a non-certified machine atmosphere monitor for CO/CO2-related warning and shutdown experimentation. The saved candidate implements CO2, temperature and relative humidity only; it does not meet the original CO/smoke/fire-response intent.
Baseline documentation snapshot: 2026-10-11, before the requested connector/protection/usability revision program. New revision features require their own reviewed source and qualification evidence.
This page documents an unqualified engineering study, not a released or tested product. Saved CAD, renders and automated checks do not establish a safe assembly, compatible cable, firmware support or a usable current rating.
Board-specific qualification limits: v11 retained strictnative/ordinaryassembly0;inherited smoke/CO function unmet,host/sourceorder/Qwiic/RF-free atmosphere/calibration/physical open.
Saved J1 mapping follows the repository contract below. Physical host and cable continuity remain unverified. J2 exposes the corresponding CHAIN nets through the declared solder links.
| Pin | Canonical role | Assigned function |
|---|---|---|
| 1 | +3.3V | +3.3 V rail |
| 2 | +5V | +5 V rail |
| 3 | GPIO! / type-specific | ALARM_IN, host-driven LED |
| 4 | type-specific | GAD_P4, chain link |
| 5 | type-specific | GAD_P5, chain link |
| 6 | type-specific | GAD_P6, chain link |
| 7 | type-specific | GAD_P7, chain link |
| 8 | type-specific | SDA_H |
| 9 | type-specific | SCL_H |
| 10 | GND | Ground |
Power off before connecting or changing jumpers. Verify pin 1, signal direction, supply voltage and ground at both ends of every cable. A mechanically fitting connector is not proof of electrical compatibility. If a host pin mapping or current allocation remains unresolved in the design record, do not connect the board until it is resolved.
The following are specification requirements or study assumptions; they are not measured operating ratings. A newer selected-revision note takes precedence over historical draft options.
The design describes the following protection intent. Check the selected schematic and remaining qualification gates before relying on it:
See current review. Retain SCD41 CO2-only/TLV75533,explicitly not smoke/CO alarm. Existing exact V2 DCK adopted v05;conditional V1 bypass/V2 reservoir families only,no successor. Current selected v11; retained native/stock/physical qualification limits remain explicit.
Use the configuration and firmware contract for the exact selected revision. Do not copy another module’s socket assignments or assume that an unused pin is available. First-article work must verify source selection, reset/unplug behavior, cable orientation and the actual load or sensor interface before normal operation.
The following are requirements for the next design iterations; this page does not claim they are already fitted:
Documentation route: smoothieware.org/extensions/smoke-detector.
The 2026-10-11 upgrade program has saved additional candidates v12, v13, v14. These studies preserve the historical design described above. Their connector, LED, mechanical and protection changes are revision-specific and remain unqualified.
See the per-board changes, failures and remaining work and mandatory family specification. Use the source hash and native check for the exact candidate being reviewed; do not infer hardware ratings from a rendered population.
The three additional revisions are v12, v13, v14. They are engineering studies; saved CAD and renders do not release the hardware. The latest candidate is described below. Older baseline notes above remain historical.
10975dc9d966688e700e7e02b5265b6a8c82bce95c603b1e2e8431fa4c790c5f.PinHeader_1x04_P2.54mm_Vertical. Fit only the selected population; check its pin map and voltage in the design record.Applicable protection, current-path, thermal, pinout, cable access and physical tests remain open wherever the linked board record has not verified them. A zero native-error count does not close those gates.
Protected source v17; current PCB SHA-256 be670139f56d8c087adffcb872ab9326952a3adf8f33403258c13eaef6062808. Fresh checks: zero enabled PCB errors/opens/parity and ERC errors; 31 PCB warnings. Electrical geometry, project rules and 50 historical files unchanged. Verified 32 model entries, 17 exports and 12 current population views, all inspected. Full documentation URL readable. CO2 monitor only; not a smoke, CO or fire alarm; inherited label/serial-field crowding and dangling conductors remain Inherited native warnings and enabled-rule exclusions remain explicit Physical/thermal/current/connector-fit qualification open No priced or area savings established by annotation candidate.