Exploring Pin Functions of MOES MS-104B 2 Gang Smart Switch with WB2S and BK7231

Hi this is my first post in this forum.

I ordered a MOES MS-104B 2 Gang Smart Switch from Amazon. As far as my research goes it wasn't mentioned or torn down so far.
There are different types out there (also with ESP8266). The one I got uses the WB2S. I was able to successfully flash the OpenBK firmware with the BK7231Flasher. However I still have problems to figure out the Pin functions (except Relay1 Relay2). It also comes with a Din Rail holder. It seems like it uses a separate Microcontroller for the Buzzer/Reset Circuit (Labelled B1PWMEH)

So at first some Teardown Pictures:


So far I found the following Pins:
Relay1: P6
Relay2: P8
Switch1: P24
Switch2: P26

I'm able to switch the Relay-Outputs via Web interface. My problem are the S1/S2 inputs. If I configure them as "TglChanOnTgl", the Relay is switched on and switched off after ~1 second (even if I keep S1/S2 connected). If I configure them as Btn they toggle the relay on every connect cycle (like a Latching switch). Any ideas?

Some Stuff on the Reset Button I discovered
When I keep the Reset-Button pressed for 5 secs, the Buzzer Beeps two times.. nothing happens
When I keep the Reset-Button pressed for 6 secs, the Buzzer Beeps two times then it toggles one relay
When I keep the Reset-Button pressed for 7 secs, the Buzzer Beeps continuously and the other relay switches on...

TheMasterFX wrote:

I'm able to switch the Relay-Outputs via Webinterface. My problem are the S1/S2 inputs. If I configure them as "TglChanOnTgl", the Relay is switched on and switched of after ~1 second (even if I keep S1/S2 connected). If I configure them as Btn they toggle the relay on every connect cycle (like a Latching switch). Any ideas?

How do you connect switch to S1? Where the other terminal goes?
Or are you trying to connect switch between S1 and S2? That would not be correct.

p.kaczmarek2 wrote:

TheMasterFX wrote:

I'm able to switch the Relay-Outputs via Webinterface. My problem are the S1/S2 inputs. If I configure them as "TglChanOnTgl", the Relay is switched on and switched off after ~1 second (even if I keep S1/S2 connected). If I configure them as Btn they toggle the relay on every connect cycle (like a Latching switch). Any ideas?

How do you connect switch to S1? Where the other terminal goes?
Or are you trying to connect switch between S1 and S2? That would not be correct.

I connected it to the live like described in the manual

Any updates on that issue? I have the same device but the input is not working. I don't know how to configure it.

How is this extra MCU connected to WiFi module? Maybe it's connected via UART? Can you do Tuya config extraction?

I found the connection layout here (similar device):
https://www.elektroda.com/rtvforum/topic3947184.html#20371671

Also, solve the issue with input. It seems like the device has a kind of AC detection which is not working with input type Btn or dInput. The only type that is working is TglChanOnTgl. Btn and dInput state flip between 1 and 0 even if you have a high on the input. It looks like the AC detection measures the 0 pass (50Hz sinus wave).

I have the same problem.

I could not find S1 and S2 inputs. Relays connected to WB2S directly. WiFi button and buzzer responses are related the external MCU behavior.
Additionally RF receiver chip is also connected the external MCU.

My guess S1 and S2 inputs are same too.

How can I analyze the situation ?