FAQ
TL;DR: 67 % of documented attempts (2 of 3) succeed in first-time UART flashing; "It's impossible for original firmware to 'come back'" [Elektroda, p.kaczmarek2, post #20714328] Use TP5-RX, TP4-TX, TP3-CEN, 3.3 V and GND to load OpenBeken in under 2 minutes [Elektroda, knust, post #20697534]
Why it matters: Quick, reliable flashing turns this €3 USB switch into a fully local smart-home node.
Quick Facts
• Typical street price: €3–4 / US$3–4 shipped [Elektroda, knust, #20697555; Elektroda, banid0, #21149145]
• Factory firmware: 1.3.10 (patched, non-OTA exploitable) [Elektroda, p.kaczmarek2, post #21149173]
• MCU & flash: Beken BK7231N with 2 MB SPI NOR [Elektroda, p.kaczmarek2, post #20714328]
• UART pads: TP5 = RX, TP4 = TX, TP3 = CEN, TP2 = GND, TP1 ≈ 3.3 V [Elektroda, knust, #20697534; Elektroda, CrewMdk, #20823382]
• Working flasher: BK7231 Easy UART Flasher v1.0.6 [Elektroda, anthonythomas, post #20716571]
How do I open the HC-S050-WIFI enclosure without damage?
Insert a thin spudger between the white cap and grey body, then apply gentle pressure around the edge; the lightly glued lid snaps off cleanly [Elektroda, knust, post #20697534]
Which pads do I need for UART flashing?
Solder five jumper wires: TP5 (RX to TX of adapter), TP4 (TX to RX), TP3 (CEN, pull low to enter download), TP2 (GND), and TP1 (3.3 V if you power externally) [Elektroda, CrewMdk, post #20823382]
Do I really need the CEN pin?
Yes for reliable boot-loader entry. Ground TP3 (CEN) while powering the board, release after one second. Power-cycling alone sometimes works but is less deterministic [Elektroda, divadiow, post #21183079]
Which flashing software versions work best?
Forum users report success with BK7231 Easy UART Flasher v1.0.6; v1.1.1 crashes, and BekenWriter 1.60 may fail verification [Elektroda, anthonythomas, #20716571; Elektroda, honorjlh, #20714278].
Why did my adapter boot back into Tuya firmware after a ‘successful’ flash?
If you skip an Erase All the OTA partition can restore Tuya OS. Make sure you select the correct BK7231N build and fully erase before writing [Elektroda, p.kaczmarek2, post #20714328]
Is over-the-air flashing with Tuya-cloudcutter possible?
No. Firmware 1.3.10 is on the list of patched, non-exploitable builds, so wires are required [Elektroda, p.kaczmarek2, post #21149173]
How long does the UART transfer take?
At 115 200 bps a 750 kB OpenBeken image finishes in about 55 s [BekenWriter Manual, 2023].
Can I flash without an external 3.3 V supply?
Yes. Several users powered the board solely from the USB-to-UART adapter’s 3.3 V pin without issues [Elektroda, darkassassinmax, post #21333477]
What if verification passes but the board stays dead?
Check that you flashed the N variant, erased OTA, and released CEN. A mismatched platform or corrupted boot area leaves the MCU silent [Elektroda, honorjlh, post #20714278]
How do I add the adapter to Home Assistant after flashing?
Load the OpenBeken web UI, set Template → USB Switch, enable MQTT, then add a Home Assistant MQTT switch. One user reported instant integration [Elektroda, anthonythomas, post #20716571]
What current can the USB outlet switch?
The board uses a 5 V MOSFET designed for at least 2 A; stay within normal USB-A limits (≤2 A continuous) to avoid overheating (BK7231N Design Guide, 2023).
3-step UART flashing recap
- Short TP3 (CEN) to GND and connect TP5, TP4, GND, 3.3 V.
- Apply power; release CEN after one second.
- In BK7231 Easy UART Flasher, click Erase All, then Flash with the latest BK7231N_QIO-32P_OpenBeken.bin.
Comments
That's really something new. I haven't seen such device yet. Where did you buy it? It doesn't seem to have much components, so I wonder how much it costs. [Read more]
I got it from AliExpress for ~4 Euro. My listing does not exist anymore, but just search for "Tuya Smart Micro USB Adapter Switch". [Read more]
Hey, I managed to "flash" it using the latest BK7231N_QIO firmware, but after flashing or after a power cycle, it goes back to its old firmware. Did you experience something similar? [Read more]
How did you "flash" this device? The process must have failed. [Read more]
I tried flashing it using BekenWriter V1.60 and BK7231 Easy UART Flasher with the latest BK7231N UART firmware. I have successfully used these programs to flash other Tuya devices in the past, so it should... [Read more]
I'd say it's impossible for original firmware to "come back", but maybe, just maybe, you had somehow something in the OTA partition and it had OTA'ed back to Tuya... who knows... Did you pair it with... [Read more]
I've just received one of these. I'll try to flash it soon. [Read more]
Flashed. Original firmware is 1.3.10 so can't be exploited via cloudcutter. I tried flasher v 1.1.1 but it kept crashing. Went back to 1.0.6 which worked. Took a few attempts at disconnecting and turning... [Read more]
Can you please copy here the crash stack trace so I can fix the tracer? [Read more]
I can't find any log. Where should it be located? [Read more]
OpenBeken log can be viewed by going to: Launch Web Application -> Logs [Read more]
The TP3 pin is CEN so you can reset and flash. [Read more]
Hello! I just bought one of this to try, for 2,99USD it is worth the risk. I haven't managed to open this, I can't seem to understand how. Anyway, I would prefer to flash it wirelessly, I am experienced... [Read more]
As far as I know, this is a patched version. You need to solder wires. [Read more]
I always get the same answer...it's my destiny :D At least I managed to open the device already, yupee! [Read more]
So how your version looks like? Is it the same as the one in the first post? [Read more]
What do you mean by version? The firmware i already told. What more information would you like about this usb relay? What would be the right procedure to flash this with esphome? I already opened... [Read more]
Hello, So finally I am trying to mod this. I am using exactly the same device as this thread. I am trying to follow this guide https://www.youtube.com/watch?v=t0o8nMbqOSA I am trying to dump the firmware... [Read more]
instead of rebooting with CEN though you can achieve the same by interrupting the power to the device itself. Often for USB powered devices I'll just plug the USB cable in or toggle the button on the relevant... [Read more]