[BK7231N /CB3S] Smoke detector MBG line VS-P443W Tuya - teardown
Name : Tuya smoke detector
Producer : MBG Line
Model : VS-P443W
Sensor purchased on Allegro for PLN 118. It has a smoke ppm indicator, battery level indicator and an alarm trigger if the smoke level is exceeded. Works with the Tuya app.
teardown:
Disassembly of the sensor is very easy - the housing is on plastic latches, and the PCB has only one screw. On the board, apart from CB3S, there is also CX32L003(F8) and it is to it, not to CB3S, that the pins RXD, TXD, GND and +3V and +3V, GND, SWC, SWD are visible.
PCB: PA-443W_V.1.1 (2021.06.15)
Microcontroller: CB3S (BK7231N)
Additional microcontroller: CX32L003F8 (ARM Cortex-M0+ 32-bit) ( data sheet )
Below soldered to PCB pins from CB3S:
Probably the main microcontroller here is ARM, and CB3S is used to receive data digitally and transmit it over Wifi. Given that it is not ESP, the only alternative may be OpenBeken, but at the moment I have no idea how to run this sensor on an alternative fw.
nihildiximus wrote 31 posts with
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Comments
Hello, thanks for showing the inside of this device. I'll try to clarify the situation. This sensor is most likely based on TuyaMCU, more specifically TuyaMCU for battery powered devices. https://developer.tuya.com/en/docs/iot/tuyacloudlowpoweruniversalserialaccessprotocol?id=K95afs9h4tjjh ... [Read more]
I pulled the sensor data through Tuya IoT Platform using API Explorer → Smart Home Device System → Device control → Get Device Specification Attribute : https://obrazki.elektroda.pl/2174461800_1684171853_thumb.jpg... [Read more]
Can you elaborate on how you got it, or write a mini-tutorial about it? One person already mentioned this, but I'm not familiar with this approach. Additionally, do you have this data in some JSON... [Read more]
I edited the post and added info on how to extract dpID (you can also use Debug device in a more limited form, but API Explorer has all the info right away). As for the GUI flasher, I don't know... [Read more]
I just added the SmokePercent channel type along with Home Assistant Discovery. Only tested on Simulator (Windows): https://obrazki.elektroda.pl/1287377100_1684171935_thumb.jpg https://obrazki.elektroda.pl/9792725900_1684171965_thumb.jpg... [Read more]
In fact, you can think about adding to this flasher or to other tools the option of extracting the dpID or even the entire configuration of the device via the Tuya API after entering the Access ID and... [Read more]
I'm posting Flasher build for testing. Make sure stock options: https://obrazki.elektroda.pl/3293560000_1684176587_thumb.jpg what do they change, and exactly, in turn, whether: 1. Does changing... [Read more]
Hi, Tuya Smoke sensor I'm just thinking loud... When only powering the CB3S with the Tuya original firmware, I get the following bytes in TuyaMCU Explorer/Analyzer: //R 07.07.2023 16:50:50 WiFi... [Read more]