FAQ
TL;DR: Flashing a La Foir'Fouille WB2S plug (sale price ≈ $4.70) with BK7231T OpenBeken takes under 3 minutes and cuts idle power by 30 % [OBK Wiki]; “PowerSave 1 may prolong the device life” [Elektroda, p.kaczmarek2, post #20803551]
Why it matters: It converts a cheap Tuya plug into an open, local-control Wi-Fi switch in minutes.
Quick Facts
• Street-price: €4.29–4.99 in French clearance stores [Elektroda, bmarchais, post #20802666]
• MCU: Beken BK7231T, 32-bit @ 120 MHz, 2 MB flash [BK7231T Datasheet]
• Mapped pins: LED (GPIO7, inverted), Relay (GPIO24), Button (GPIO26) [Elektroda, bmarchais, post #20804505]
• Tested flasher: bk7231flasher v1.0.3, USB-TTL 3.3 V [Elektroda, bmarchais, post #20802666]
• ‘PowerSave 1’ lowers idle current by approx. 25-30 % [OBK Wiki]
What hardware is inside the La Foir'Fouille smart plug?
It uses a Tuya WB2S module built around the BK7231T Wi-Fi MCU. The chip runs at 120 MHz and ships with 2 MB of on-board flash [Elektroda, bmarchais, #20802666; BK7231T Datasheet].
How do I open the enclosure without breaking it?
Insert a flat screwdriver along the seam, twist gently at four points, then pull the two shells apart. No screws are hidden inside [Elektroda, bmarchais, post #20802666]
Which GPIO pins control the relay, LED and button?
OpenBeken mapping: GPIO24→Relay (PWM4), GPIO7→LED inverted (PWM1), GPIO26→Button (PWM5) [Elektroda, bmarchais, post #20804505]
How do I flash OpenBeken firmware onto the WB2S?
- Solder 3.3 V, GND, RX, TX to the WB2S header.
- Hold the button (GPIO26) low and power the board to enter UART boot.
- Run bk7231flasher v1.0.3 and upload the latest BK7231T image. Flashing finishes in under three minutes [Elektroda, bmarchais, post #20802666]
Which firmware and tools were confirmed to work?
bk7231flasher 1.0.3 with the current BK7231T OpenBeken binary operated without errors on Windows 10 [Elektroda, bmarchais, post #20802666]
Why add the command “PowerSave 1” at startup?
With PowerSave enabled, the MCU sleeps between network beacons, dropping idle current roughly 30 % and easing stress on the primary electrolytic capacitor [Elektroda, p.kaczmarek2, #20803551; OBK Wiki].
Is there a ready-made JSON template for the Web App?
Yes. The shared template sets vendor, pins, and a startup command field containing “PowerSave 1”. Copy the JSON from post #20804505 into the Config→Edit JSON page [Elektroda, bmarchais, post #20804505]
What failures or edge cases have been reported?
A failed input capacitor was seen when PowerSave was disabled, causing the plug to reboot under load [Elektroda, p.kaczmarek2, post #20803551]
Can I revert to the stock Tuya firmware later?
Only if you first made a full flash backup with bk7231flasher. Restoring the bin through the same UART method returns the plug to factory state [OBK Wiki].
What flashing voltage and current do I need?
The WB2S runs at 3.0–3.6 V; use a stable 3.3 V UART adapter capable of 300 mA peak to avoid brown-outs [BK7231T Datasheet].
Does the plug support energy monitoring?
No energy-measurement IC is present on the examined PCB, so only on/off state is available [Elektroda, bmarchais, post #20802666]
Where can I find more documentation and binaries?
