【Intelligent hardware】Heating table

One project requires

the basics of Arduino-C language;
the use of LEDC, ADC, and IIC peripherals of esp32;
the correct use of Lichuang Eda drawing & PCD, and placing unit devices in Lichuang mall;
development using vscode+platformio.

2. Completed functions
2.1 UI interaction
This project was made with reference to the peng-zhihui/OpenHeat project. In order to facilitate welding, the esp32 chip of the original control board was abandoned and replaced with an esp32 module and pin to pin modified board. It has the same operating logic as the original system. Rotate the encoder left and right to select, press to confirm, and long press to return.
2.2 Hot bed
reference GS_Hbed
PCB trace resistance calculation formula: R=ρL/(1000*WD)ρ is the resistivity of copper: ρ=0.0175Ωmm^2/mL is the trace length: unit mmW is trace width: unit mmD PCB copper thickness: 1oz copper clad plate copper foil thickness is 0.035mmeg: 1mm wide and 100mm long trace resistance is R=ρL/(1000*WD)=0.0175*0.1/(0.035*0.001*1000)=0.05Ω= Calculation of the length of the 50mΩ
Hilbert curve: The total length l, the order is n, the unit length is d, the total length is l = (2^(2n) -1)*d. Use the Hilbert curve to cover a square, then the large square Each
    design parameter: 3Ω/0.75Ω, (12/24)V 192W, 12V48W PCB wire total resistance is 3Ω.
    Known variables: 1. Hilbert curve coverage size S=L * L= about 110mm*110mm 2. Total Resistance: 3Ω 3. Resistance calculation formula, curve length formula (order, unit length) Unit length of 6th order curve: d= L/(2^n) = 110/(2^6) = 1.71875mm, value unit length The total length is 1.72mm: l = (2^(2n) -1)*d = 7043.4mm=7.0434m.
    The wire width is derived from the obtained wire length. R=ρL/(1000*WD)=0.0175*7.0434/(0.035*W*1000) =3 Ω Calculated: W = 1.1739 mm, value 1.17mm, calculated resistance: 3.01, predicted actual resistance is 2.7Ω, Peak power 213W
Three installation methods
The base plates are connected together by wires to connect the copper-plated parts of the middle layer.
The hot bed is connected to the middle layer through copper pillars.
Use the on-off switch of a multimeter to measure the connection. If there is no problem, you can connect the uab-c/uab-b interface and burn the program first (16PIN usb-c is not easy to solder.