Nous A8M Smart Plug Tuya T34 BK7231N OpenBeken Flashing Experience & Power Data Delay

I purchased some Nous A8M smart plugs because they advertised matter support and I thought that would make it easy to integrate them into HA without flashing them.

However I discovered that the matter implementation is very bad (power measurements are delayed by up to 30minutes)


So I opened up one plug to see if it can be flashed




It uses a Tuya T34 chip based on BK7231N and sadly does not expose any programming pads.
However with a lot of patience I was able to solder some very small wires to the chip and flash it with open Beken.

The device chips with a special 3.0 bootloader, to get the ota feature to work i flashed an old 1.01 bootloader.

Sadly it does not quite work correctly:
I can control the relay and get power measurements. As long as the device is already plugged in while the plug boots.

However when I plug something into the plug, the the firmware immediately reboots and the WiFi led flashes.
In the stock firmware everything works fine.

The generated openBK config is as follows:

Device configuration, as extracted from Tuya:
- BL0937 SEL on P14
- Button (channel 1) on P7
- BL0937 VI (CF1) on P26
- WiFi LED on P8
- BL0937 ELE (CF) on P24
- Relay (channel 1) on P6
Device seems to be using T34 module, which is using BK7231N.
And the Tuya section starts at UNCOMMON POSITION 2052096





Does someone have an idea what might be the issue?

Does the reboot happen if you use OBK with clear config (no relay, led, power measurement) driver?

Does the reboot happen if you enable PowerSave? PowerSave 1

>>21701126

I think it was not a software issue.
I disassembled and reassembled the smartplug and now it no longer reboots when I plug something in it.
Maybe something was wrongly oriented inside the first time?

Maybe something was shorting VDD to ground.