V1.2 ESP32 solar water heater connected to Homeassistant

2022.11.25 update: The V1.2 version of the board file has been updated with a small BUG. The I2C interface can use the default 4 and 5 interfaces. It was previously modified to RX and TX, and there is a BUG.
Some time ago, I was browsing a forum and saw a netizen asking how to use ESPHOME to obtain the temperature and water level of a solar water heater. It just so happened that I had just added a controller to the solar water heater at home, so I might as well make one. In order to save costs, I used Hezhou's ESP32C3 board. The 12.9 free shipping is really good, but there are pitfalls. ESPHOM is too tricky to compile, and the pinout diagrams provided by a certain store are all wrong. Finally, in the official website information I found the correct one, but I had to change it several times. It was really a mess. This board is cheap, and it’s pretty good for LuatOS. It is basically perfect at present. It uses the 4-wire sensor that comes with the original controller to display water temperature, water level, water filling feedback, and heating feedback synchronously with the original controller. It can also control automatic water filling and automatic heating without affecting each other's functions. The water temperature display differs by ±2°C from the original controller. If you are pursuing perfection, you can fine-tune it in the code. As for the water level display, my sensor seems to be different from the ones on the market. The resistance value is inconsistent with the information on the Internet, but it is correct when used in my code. The display is accurate at the moment. Temperature compensation will be added to the code later to make it more accurate. . Finished product demonstration: https://www.bilibili.com/video/BV1PW4y1W7hF/?share_source=copy_web&vd_source=bb9fad492beb562a51ae934524bc0475 This is the HA display page, which can be controlled and has feedback. (Attention!!! There is 220V strong electricity in the controller! Operate with caution! All operations are performed after the power is turned off!!!)
(Attention!!! There is 220V strong electricity in the controller! Operate with caution! All operations are performed after the power is turned off!!!) ! ! )
(Attention!!! Controller measurement and wiring require basic circuit knowledge. For safety reasons, use an idle router or other 12V power supply to connect the positive and negative poles to the 12V wiring in the controller. This allows the controller to be turned on without connecting to 220V, which facilitates our wiring and experiments (the output voltage of the transformer of different controllers is not necessarily 12V, please refer to the actual measurement.)