ESP8266_Washing machine washing timer

The reason was that the timer function of the washing machine at home was broken. It was a bit difficult to find the same model of timer online, so I directly made an electronic timer controlled by a microcontroller.
 
The type of washing machine in my home is as shown in the picture below:
 
As shown in the picture, this type of washing machine is an older double-tub washing machine. The left barrel provides forward and reverse rotation and timed washing functions, and the right barrel is for spin drying. This item is used to replace the left barrel. function.
The functions of this type of washing machine are generally set and used through the upper knob, and this project replaces and uses that knob.
 
 
The equipment produced using this project needs to be powered by a 12V-DC power supply. The power supply type is as follows:
 
 
The input terminal of the 12V power adapter is connected in parallel with the washing machine power input terminal (220V), and the output terminal of the 12V power adapter is connected to the device for power supply.
 
The actual picture of the equipment is as follows:
 
 
Equipment description:
 
This equipment is an electronic timer made by ESP8266EX as the main controller to replace the washing timer function of the washing machine. Its pin definitions are as follows:
 
 
1. Reserved holes for microcontroller program burning: Upper There is a 1x5p 2.54mm binding post in the upper right corner of the picture, which is used to program the device. Its pin definitions have been marked. Please learn how to program the ESP8266EX by yourself.
 
2. MCU reset button RST: When the button is not pressed, the MCU RST pin is high level. When pressed, the pin is pulled down, so the MCU restarts. It is used to restart the MCU during debugging.
 
3. Equipment power input: There are two power input methods on the left side of the circuit board, which are suitable for DC head or wire welding. You can choose according to your own power adapter. The power input should be between 12V-6V. It is recommended to use a 12V power adapter. .
 
4. Power switch in the upper left corner: This switch controls the power switch of the device and has been marked with silk screen on the side.
 
5. Operation panel: This board is used for function settings. The actual picture is as follows: Click here to jump to the open source link of the operation panel.
 
 
As shown in the picture above, the operation panel has a two-digit digital tube and a micro switch. This combination can be completed. For the control of the washing function, the operation panel is connected to the operation panel power supply, data interface and other pins on the equipment board. The corresponding relationship is as follows: if
you cannot see clearly, you can directly look at the PCB file, which is clearly marked.
 
 
6. Relay interface: There are two relay interfaces on the right side of the device:
 
 
The definitions are as follows: 
 
 
The relay interface corresponds to the relay module. Let’s talk about relay selection:
When choosing a relay module, please select the following specifications: 5V voltage input, low level trigger Suction.
 
 
The above may not explain clearly how to realize the function of the equipment, please continue to read below:
 
When I removed the broken washing timer, I found that there were three wires connected to the timer. After measuring with a multimeter and short-circuiting test, I found that among them One is a live wire, and the remaining two are forward and reverse control wires. If the live wire is connected to one of them, it will turn left, and if the live wire is connected to the other, it will turn right.
From this, a relay can be used to realize this function. Please see the picture below:
 
 
The picture above is a schematic diagram of the connection of these three lines. The dark brown line marked in green is connected to the bright red line, which can be regarded as one line, and the yellow and black are Motor forward and reverse control lines.
The NC terminal of the two relay modules is vacant, the live wire is connected to the COM terminal, and the NO terminal of the two relays is connected to the forward and reverse control lines of the two motors respectively. This line can be connected to any NO terminal regardless of the order.
Please make sure that the live wire is not connected to the two control wires at the same time, otherwise the motor may be burned. Please tighten the screws when connecting the relay module.
 
Adjustment of the upper limit of the washing time setting in the program:
When I wrote it, I had programmed 20 minutes as the upper limit of the washing time, but it does not rule out that everyone needs a longer washing time. You can modify the number size in the picture below to obtain a longer washing time. But please do not exceed 100, as it will cause display abnormalities:
 
 
Function demonstration description: As can be seen in the video, after clicking the button, the washing time displayed on the digital tube becomes longer. When the washing reaches the preset maximum value, it returns to 1 minute to reach the ideal value. Finally, double-click the button to start the washing mode. The digital tube display switches between the set value and 00, indicating that washing is in progress. When the washing time is reached, the digital tube stops flashing and the washing bucket stops rotating. Note that I did not write a stop function. I would have to cut off the power supply of the washing machine if I wanted to stop it in the middle.