Firmware

Release notes, signed binaries and OTA instructions. Updates are free for the life of your controller — no forced pushes, no paid unlocks, no cloud required to install.

Our firmware pledge: Free OTA updates forever. You initiate them — we never force. Every customer runs the same firmware — no paid tiers. If a future version adds something you don't want, stay on your current version indefinitely; your controller will keep working.

Binary downloads land on launch day. Between now and batch-1 delivery we're finalising the signed-OTA pipeline (v1.6) on the production PCB from UC Industrial. Release notes below are the canonical record of what shipped in each firmware version. The .bin files become downloadable here the moment batch-1 goes out.

v1.5.4 Current Released 18 April 2026

What's new

Bud-rot (Botrytis) risk detection — monitors night-time RH × VPD window, force-raises extract to ≥80% and pushes mobile alert when conditions favour grey mould.
SCD41 replaces SCD40 for CO₂ sensing — extended 400-5,000 ppm range, tighter ±(40 ppm + 5% m.v.) accuracy, better on-chip T/RH compensation.
Environment score tuning — less penalty for pH outliers during feed days, more weight on sustained VPD drift.
REST API v2 docs at /api/docs on the controller (interactive).

Fixes

Soil-probe Modbus retries no longer block the main loop on dropout.
OTA progress bar now updates correctly during the checksum phase.
Heap-leak under sustained MQTT reconnect storms — closed.

Nexus firmware (1.4 MB, pending) Router firmware (Mini / Mid / Max) (0.9 MB, pending)

v1.5.0 Released 12 March 2026

What's new

Week-by-week grow plans — 4 plan slots × 16 weeks each, auto-advance every 7 days, per-week VPD/temp/RH/CO₂/DLI/lights targets.
BudMaster Mobile App with inline-keyboard controls — 22 commands, zero-config chat linking.
Dual-safety CO₂ cutoff — software 30-second cap + independent hardware ISR 35-second backup.

Nexus firmware (archive) Router firmware (Mini / Mid / Max) (archive)

v1.4.0 Released 4 February 2026

What's new

0-10V LED dimming output with closed-loop DLI control (PAR sensor feedback trims driver to hit daily target).
RS-485 Modbus soil probe support — 7-in-1 industrial probes on the Nexus hub.
Local MQTT + Home Assistant integration (optional, disabled by default).

Nexus firmware (archive) Router firmware (Mini / Mid / Max) (archive)

v1.3.0 Released 10 January 2026

What's new

VPD-driven automation baseline — fan modulation holding target VPD range.
Triple-sensor pod at launch: AHT20 (T/RH) + BMP280 (pressure) + SCD40 (CO₂).
Smart-plug integration — 4 channels (humidifier, dehumidifier, heater, cooler).

Nexus firmware (archive)

How to OTA-update your controller

Download the correct .bin for your model from the section above.
Verify the SHA-256 checksum matches the one listed beside the download (optional but recommended).
On your controller dashboard, go to Settings → OTA Update.
Drag the .bin file into the drop zone, or click to browse.
The controller verifies the signature, flashes, and reboots. Takes about 30 seconds.
After reboot, check Settings → About to confirm the new version number.

If anything looks wrong after an update, the previous firmware is held in a fallback partition — power-cycle and tap the reset button three times within 10 seconds to roll back.

No internet on your controller? OTA works fully offline — download the .bin on another machine, transfer via your local network, flash via dashboard. We never need to see the traffic.

For developers — source code + build

The BudMaster firmware is open-source. Repository: github.com/betysmalls/budmaster (FIRMWARE/ directory). Built with Arduino IDE + ESP32 core 3.3.7. PlatformIO configuration also shipped.

To build your own variant:

Clone the repo. Install ESP32 core in Arduino IDE.
Open FIRMWARE/BudMaster_Nexus/BudMaster_Nexus.ino (or the Router_Mini / Router_Mid / Router_Max variants).
Optionally define CARRIER_V2 for the production-PCB pin mapping.
Select board "ESP32-S3 Dev Module", upload via USB or OTA.

Pull requests welcome. We don't gate contributions behind a CLA; your commits stay yours.