Developer mode

Developer Mode

The bcMeter interface includes a hidden developer mode for advanced hardware tuning and diagnostics. Changes in developer mode affect hardware directly — only modify settings if you understand their impact.

Activating Developer Mode

1. Open Settings (gear icon).
2. Click on the device name text (next to "Configuration") 7 times within 3 seconds.
3. The name will change to show [DEV] in yellow.
4. A new Developer tab appears in the settings panel.

Developer mode persists until the page is reloaded.

Developer Settings

The Developer tab exposes low-level configuration organized into sections:

Calibration (dev:calibration)

Parameter	Description	Default
LED duty cycle (880nm)	Brightness of the 880nm IR LED (0–255)	Auto-set during calibration
LED duty cycle (520nm)	Brightness of the 520nm green LED	Auto-set
LED duty cycle (370nm)	Brightness of the 370nm UV LED	Auto-set
Calibration factor K (per channel)	Ratio Ref/Sen from last calibration	Auto-set
LED duty floor	Minimum duty before "no filter" is declared	30

Optical (dev:optical)

Parameter	Description	Default
Sample spot diameter	Diameter of the filter area exposed to sample air (cm). Critical for absorption calculation.	0.4 cm
Filter scattering factor	Correction factor for filter material light scattering	1.39
Number of channels	Active wavelength channels (1–3)	1 (880nm only)

Pump (dev:pump)

Parameter	Description	Default
Pump duty cycle	Base pump PWM speed (0–255)	40
Min pump duty	Minimum duty to maintain airflow	35
Max pump duty	Maximum pump speed limit	255
Min airflow (mL)	Stall detection threshold	70 mL/min
PWM frequency	Pump control frequency (Hz)	40
Disable pump control	Manual mode — bypasses automatic pump management	false
Enable 12V output	Activate 12V auxiliary power rail	false

Auto Flow Control (dev:afc)

Parameter	Description	Default
AFC flow low	Minimum airflow when AFC is active	0.05 L/min
AFC flow high	Maximum airflow when AFC is active	0.5 L/min
AFC BC low/high	BC concentration thresholds for flow lookup table	Varies

Hardware (dev:hardware)

Parameter	Description	Default
is_ebcMeter	Enable direct emission mode (µg units instead of ng)	false
IoT enable	4G/LTE modem available	false
Enable WiFi	WiFi connectivity available	true
Show undervoltage warning	Display warning when 12V rail not detected	true

System (dev:system)

Internal system parameters. Modifying these may affect device stability.

Development Build Detection

When the device is running a development build, the API returns "env":"dev" in the status response and a red banner appears at the top of the interface:

DEVELOPMENT BUILD — connected to dev backend

12V Power Warning

If the optical ADC is not detected (because 12V power is missing), a warning modal appears:

⚠ 12V Power Missing — The optical ADC is not detected. Optics and light sensors will not function. Pump and airflow control (5V) are unaffected.

Onboarding Skip Mechanism

The welcome/onboarding screen can be bypassed:

• Skip for now: Hides for 2 days (stored in localStorage + cookie).
• Don't show again: Permanently disables onboarding by writing onboarding_done: true to device config.

Identify Device

The Developer tab includes an Identify Device button that blinks the status LED in a distinctive Morse code pattern (spelling "bcmeter") for 30 seconds. This helps visually locate a specific device when multiple units are deployed in the same area.

• API call: /api/control?action=identify
• Duration: 30 seconds
• Pattern: Morse code at ~10 WPM (dot = 120 ms, dash = 360 ms)
• LED reverts to its previous mode (idle, sampling, or error) after the pattern completes.