Flashing the CB3S chip

Hardware
1

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I have now purchased my Tuya EARU breaker 3P+N for the second time, as the first one went into “standby” mode, switched through but no longer read the live data.

I decided to flash this second breaker in order to integrate it into Home Assistant.

The breaker contains the WiFi module with the CB3S, which can be flashed with the OpenBeken tool BK7231GUIFlashtool.

I did everything necessary for flashing and followed the instructions I knew. But the flashing process did not work. I don’t know why, maybe I killed the module. I don’t know. When idle, it draws approx. 40 mA at 3.3 V, which seems normal to me.

I read somewhere that you have to try more than once. Can anyone confirm this before I give up for good?

2

I did it.

The USB-TTL adapter with CH340G had an 8-pin header, and there are several configurations for this adapter (headers) on the internet, and I picked the wrong one. I did a local loopback and determined the Rx that way. The Tx was correct.

Then everything went smoothly.

Now the really interesting work begins…