logo elektroda
logo elektroda
X
logo elektroda

[BK7231N CBU] Generic Temperature and Humidity Sensor

Chasbrot 
Hi! Here is a teardown of a random super generic temperature and humdity sensor from aliexpress.

Bought From:
https://de.aliexpress.com/item/1005004854419532.html
Wifi Version, really quick delivery to austia ~ 2 weeks

Pictures:


Device Pinout:


Datasheets:
uC: https://developer.tuya.com/en/docs/iot/cbu-module-datasheet?id=Ka07pykl5dk4u
SHT30: https://sensirion.com/media/documents/213E6A3B/63A5A569/Datasheet_SHT3x_DIS.pdf
Specific Device ID: SHT30 DIAS7M

Flashing:


I could flash latest BK7231N Image via console.


Config:


Driver for SHT30 is missing but i have created a github issue:
https://github.com/openshwprojects/OpenBK7231T_App/issues/574

About Author
Chasbrot wrote 1 posts with rating 7 . Been with us since 2023 year.

Comments

p.kaczmarek2 01 Jan 2023 13:10

Thank you for posting this. I can see that's a battery powered device. We need to enable power save in order to save battery. First of all, please add "PowerSave" command to short startup command, but... [Read more]

gulson 02 Jan 2023 11:03

Thank you for your publications. I am curious how long the battery will last after changing the firmware and will there be a low battery notification? I wonder if the device can operate on 2 x AAA rechargeable... [Read more]

speedy9 02 Jan 2023 13:48

I have a similar sensor (I don't know if it's the same because I haven't disassembled it). On new good batteries it works 2-3 weeks depending on the temperature. It is worth mentioning that... [Read more]

lionboy 03 Jan 2023 22:27

Hello, anyone figured out how to config this device to show temp , humidity, battery lvl? [Read more]

p.kaczmarek2 04 Jan 2023 00:06

@lionboy if you have the same device type, you should wait for the implementation for two things: - deep sleep (so batteries won't drain fast). Current "powerSave" command will not be enough for that -... [Read more]

lionboy 04 Jan 2023 09:44

I have the same sensor, i wll wait until fix the problem, is flashed but no problem, i saw from last night until now battery is empty :D [Read more]

p.kaczmarek2 04 Jan 2023 10:36

Our team member and contributor, @btsimonh , has received a battery-powered PIR sensor (CBU module) few days ago with no MCU. He will be most likely looking into supporting that as well. [Read more]

btsimonh 05 Jan 2023 09:35

Mine is 3 x AAA powered, 'N' based (CBU). I bought it 2nd hand on ebay, just so I had one :). But no manual or mountings. Looking at a manual online for a similar device, they claim 5 months on 3 x... [Read more]

nelliug54 06 Jan 2023 21:38

Hi everibody, I'm new on the forum, I have some experience in "brain changes" to convert tuya devices to local control with Tasmota. At this moment I'm focussed in fotovoltaic generation and home energy... [Read more]

p.kaczmarek2 06 Jan 2023 22:58

There is no datasheet, just our own research. But we have that: https://obrazki.elektroda.pl/8109819400_1673043809_thumb.jpg And that datasheet (but it's not BK7231 chip datasheet, but for module): https://www.elektroda.pl/rtvforum/download.php?id=1133903 How... [Read more]

dheenhasty 14 Jan 2023 15:57

Hello, new on this forum. i have publish a merge request to add the sht3X support. it works but measurement is not ideal even if i have taken the constructor reference for the sht3X. i support that... [Read more]

p.kaczmarek2 14 Jan 2023 16:55

Hello, very good job. I will llook into your code, but have you considered using PowerSave command to reduce current consumption and lower heating? [Read more]

dheenhasty 14 Jan 2023 17:07

Yes it's activated at the init of the script. And i activate tuyamcu who suppose to deactivate wifi when not needed. For the moment the battery voltage is pretty stable. i have tested the measure... [Read more]

p.kaczmarek2 14 Jan 2023 18:42

But that would be a per-device calibration? [Read more]

dheenhasty 14 Jan 2023 19:16

I don't know it's a supposition .... maybe a missread the documentation and you have some sort of calibration that can be done at init ..... So batterie Died in 6h with a 10 min refresh. Will try... [Read more]

p.kaczmarek2 15 Jan 2023 08:51

@btsimonh , any progress with deep sleep? There is an API for deep sleep in the Beken SDK but I am not sure if I should point you towards it, @dheenhasty . If you enable deep sleep, then you might end... [Read more]

dheenhasty 15 Jan 2023 15:56

I have try to compile for the 8371N, but seems like the SDK is broken for the powe_save once i activate the manual power saving flag: beken378/func/power_save/manual_ps.c:190:20: error: 'SCTRL_LOW_PWR_CLK'... [Read more]

p.kaczmarek2 15 Jan 2023 16:22

I have tested it only for BK7231T. Here is the only change needed to compile: https://obrazki.elektroda.pl/2617583000_1673796073_thumb.jpg If you are compiling for N, and for example SCTRL_LOW_PWR_CLK... [Read more]

nelliug54 16 Jan 2023 10:28

@dheenhasty Very good job Here is the shematic. https://obrazki.elektroda.pl/9879827700_1673859980_thumb.jpg I think a new massurement could be taken, that is battery voltage. Just putting... [Read more]