FAQ
TL;DR: 13 A single-channel FUT036W drivers can be tamed with OpenBeken 1.15.663; “dual-MOSFETs share one PWM for higher current” [Elektroda, p.kaczmarek2, post #20521323] Configure PWM pins, Smart-Button roles, and Flag 12 correctly to restore full web and local control within 3 reboots. Why it matters: avoids dead-LED and overheating faults in camper lighting.
Quick Facts
• FUT036W rating: 12-24 V DC, 13 A max [Elektroda, mplum, post #20521163]
• BK7231 chips expose 6 hardware PWM pins; others flicker [Elektroda, p.kaczmarek2, post #20521194]
• OpenBeken build fixing multi-PWM UI: v1.15.663 (7 Apr 2023) [Elektroda, mplum, post #20529781]
• TuyaMCU UART baud: 9600 bps typical (“simple protocol”) [Elektroda, p.kaczmarek2, post #20521194]
• Flash endurance: ≥100 k erase cycles; OBK slices writes to 64 B, extending life ×128 [Elektroda, p.kaczmarek2, post #20554657]
Why does the web slider disappear when I map two MOSFETs to one PWM?
Prior to build 1.15.663 the UI counted GPIOs, not channels, so it exposed a CCT slider and zeroed channel 0. Update to ≥1.15.663 or newer to restore a single dimmer slider and synced outputs [Elektroda, p.kaczmarek2, #20527576; mplum, #20529781].
Can one PWM gate two parallel MOSFETs safely?
Yes, if both MOSFETs share the same gate resistor and are rated for the combined current. They are factory-paralleled for 13 A LED strips; just tie both gates to one hardware PWM pin to keep smooth dimming [Elektroda, p.kaczmarek2, post #20521323]
Smart-Button long-press turns brightness to zero—how do I stop the wrap-around?
Use SetButtonTimes to speed repeats and DimmerDelta to fix the step size, then script a channel flag that toggles direction: 1. OnHoldStart→ToggleChannel 10. 2. OnHold→add_dimmer $CH10 1. 3. ClampChannel 0 5 100 to cap at 5–100 %. This prevents crossing 0 % [Elektroda, mplum, post #20552740]
LED will not light after enabling Flag 12 (SaveState). What’s the edge case?
If you enable Flag 12 and reboot before changing brightness once, OBK stores an empty state and channel stays at 0 on every boot. Dim or toggle once, then reboot; the valid state is saved and control returns [Elektroda, mplum, post #20559643]
Does frequent dimming wear out flash with Flag 12?
Unlikely. OBK writes 64 B pages inside a 4 kB sector, giving ~128 writes per erase. With 100 k erase endurance your controller survives ≈12.8 M state saves—years of daily use [Elektroda, p.kaczmarek2, post #20554657]
How do I clone all settings to another CB3S safely?
- On source, download OBK CFG (excludes Wi-Fi & LFS). 2. Download TAR backup of LittleFS. 3. On target, upload CFG, reboot, then upload TAR. This keeps macros, scripts and GPIO roles while preserving unique RF calibration [Elektroda, p.kaczmarek2, post #20564121]
One unit ignores the first Device-Group command after being idle. Fix?
Send the group packet twice or append a 0.1 s delay: DGR_SendPower All_on 1 1 ; delay_s 0.1 ; DGR_SendPower All_on 1 1. Build ≥1.17.54 improves reliability; disable PowerSave if latency persists [Elektroda, p.kaczmarek2, #20553231; #20557126].
Is DS18B20 temperature sensing supported yet?
Not yet. Current builds only read DHT11/22. DS18B20 is on the TODO list, so use a DHT11 module for now [Elektroda, p.kaczmarek2, post #20521459]
BK7231 board won’t enter recovery after five power cycles—hardware dead?
Check UART TX2 at 115200 bps. If no boot banner appears yet the MCU still reads/writes flash, RF section may be damaged. Replace module; software recovery depends on valid RF calibration [Elektroda, p.kaczmarek2, post #20573784]
Quick 3-step: map two GPIOs to one PWM channel
- In Configure GPIO set both output pins to PWM1. 2. Update firmware to ≥1.15.663. 3. Reboot; both MOSFETs mirror channel 0 brightness without extra scripting [Elektroda, p.kaczmarek2, post #20527576]
How to broadcast central OFF without Home Assistant boot delay?
Use local scripting: addEventHandler On3Click 6 backlog DGR_SendPower All_on 0 1 ; POWER OFF. Every node receiving the UDP packet switches off within 200 ms without MQTT or HA [Elektroda, mplum, post #20550779]
What’s the correct baud and pins to sniff TuyaMCU packets?
Wire Tuya TX to BK RX2 and set UART 1 to 9600,8-N-1. Capture hex frames, then map datapoints for custom support [Elektroda, p.kaczmarek2, post #20521194]
