Shenzhen Manhe Intelligent WB01 Single-Gang Touch Switch from Manhot Store on AliExpress [BK7231N]

Hi. Here's a quick look at a nice easy single-gang touch sensitive switch. Going on the printed label on the box, it appears to be from Shenzhen manhe Intelligent Technology Co., Ltd.

It was from the Manhot Official Store on Ali Express https://www.aliexpress.com/item/1005005912896498.html




Curiously it comes with an additional MCU but I don't think the BK7231N knows about it. There are no communications I could detect with TuyaMCU Analyser and the config extraction makes no mention of one or a baud rate. tuyaMcu_sendQueryState returns no result. I think the MCU is just changing the status of the red/blue switch LED on touch panel contact which is not referenced in the extracted config. The only LED in user_params is the wifi status.

- Button (channel 1) on P24
- WiFi LED on P6
- Relay (channel 1) on P20



Possibly it would have a greater part to play depending on what these missing components are


Using that product key in a search reveals a selection of similar devices, though most seem to have a CB3S module (which is also referenced in the json for this device), which this unit clearly does not have.

To the extent of flashing OpenBeken, these test pads were traced and UARTs used successfully


None of the test pads are UART2, so boot log was captured with a sewing needle connected directly to the UART2_TXD pin of the BK7231N, T34 stylee.



v1.3.5 known patched = no cloudcutter.

In the gang of 4 test pads at the bottom, the middle two were tested for JLink SDA connectivity but they do not appear to be so.

To aid me in tracing I made this to orient myself.



Upon flashing and import of the extracted config we have a 100% working device with behaviour like that of the factory firmware.

-button backlight and wifi LED flash when connecting to wifi and then solid blue when connected
-switch off = blue backlight hue
-switch on = red backlight hue

personally, red signals off for me, but I guess red could also be interpreted as "hot", live, on.




Template




https://github.com/OpenBekenIOT/webapp/pull/134

Hello @divadiow Thank you for the write up, I came across this recently and because of your detailed instructions I decided to order this switch, however I have been trying to follow your instruction to flash it but I have not had any success so far, please how do I get it to enter flashing mode? Thank you

hi. OK. how long are your wires from device to USB-TTL adaptor? How are you supplying the 3.3v to device? If you have pics of your setup that would definitely help.

Thank you, the data wires are short, I used external power from a 12v adapter and a buck converter set to 3.33v. I couldn't get it to flashing mode no matter how many rebooting I did, and I also couldn't recognize CEN on the board to ground, easy flasher was set to 115200 baud rate, attached are some pictures

I'm in daylight on my phone at the moment so the pic is a little hard to make out but do I see the USB-TTL not in common ground with the ext PSU?

Thank you, sorry about the picture, yes the USB-TTL GND is not connected to the ext PSU GND, is it supposed to be?

Yes. Common ground with device, usb adaptor and psu

Thank you so much for your help, this still doesn't work for me, please can I use tuya-cloudcutter

depends what firmware version your device came with. https://github.com/tuya-cloudcutter/tuya-cloudcutter/wiki/Known-Patched-Firmware

What's going on with the UART flashing method?

Are you confirming the power is enough to power your device? As in, with power applied do you get a booting/working device?