[Solved] [BK7231N - CBU] WD-01ADE Tuya water pump with WiFi: Pin Configuration,Btn

Tuya water pump with WIFI

Source: aliexpress
>WIFI Control Plant Drip Irrigation Watering System Kit Garden Automatic Watering Device Pots Double Timed Water Pump



The watering system is controlled by Tuya module CBU (CBU-NL) -> BK7231N
(Earlier devices are built with ESP8266)

All needed pin are accessible. You can flash it without dismount the module.


Pin definition for the module as cbu.txt

The device works with four batteries or with USB-Cable.

These pins are used:
P16 - REL1 - pump-A
P14 - REL2 - pump-B
P8 - Btn_n 1 - for pump-A
P7 - Btn_n 2 - for pump-B
P20 - WifiLED

I run it with the autoexec.bat attached.

Some inner pictures:




Also the Tuya configuration is added here as zip.

The measured power consumption is:
72mA - quiescent current
280mA - with one running pump
490mA - with two running pumps
It is not a good idea to run it on battery without energy saving rules.

There is one problem with the configuration: I must press the button twice to start and stop the pumps.

The device requires a very good power supply.
To make the function safer, I soldered a backup capacitor between 0 and 3.3V (470uF).

Hello, are you sure it's Btn_n (button between GPIO and VDD) and not Btn (button between GPIO and GND)?

You can lower the current usage by using PowerSave 1 command in OpenBeken, put it in short startup command or in autoexec.bat.

Anyway, thank you for an interesting review. I haven't seen this device yet.

Hello,
Yes, I am not absolutely sure about the question Btn / Btn_n.

For exploration, I set the input to a separate channel.
Btn_n gave me
unpressed -> channel=0
pressed -> channel=1
That is why I defined Btn_n.
Andreas

Hi,

Any chance that someone can write a short documentation on how to flash this device? I soldered TX1, RX1, GND, and 3V3 and connected it to USB. But I am stuck at this part where you have to power off the device or short circuit GND and CEN.

How can I power off the device?
(it seems that I am too clumsy for the 0.25s short-circuiting of CEN and GND)

Power off by disconnecting 3.3V from the device and reconnecting it again.

You can also do the following:
1. disconnect 3.3V from the device
2. the 3.3V wire that goes still to the device now can be shorted to ground for a short amount of time (not the wire from power supply!)
3. reconnect 3.3V

Hi drkbg,

Please excuse the late answer.
In my case, I use a short connection between CEN and ground.

Please do:
- Connect GND, Vcc, TxD, RxD to the RS232-Interface
- Start the transmission (uartprogram --unprotect -w ...)
- Make a short-time connection from CEN to ground
-> The transfer is starting immediately.

Sometimes I had to repeat it, but most of the time it works.

Andreas

Please do:
- Connect GND, Vcc, TxD, RxD to the RS232-Interface.
- Start the transmission (uartprogram --unprotect -w ...).
- Make a short time connection from CEN to ground.
-> The transfer is starting immediately.