Introduction

This project uses stm32 microcontroller and tuya's wifi module. stm32 collects temperature and humidity. The temperature and humidity module uses SHT71, which is displayed in real time through OLED or digital tube. When the temperature is lower or higher than the set temperature, the external heater can be controlled through the control relay. Heating or prohibiting heating, and using the tuya module to connect to the cloud, the temperature and humidity can be monitored in real time through the mobile APP.

Features

Key function: supports single click, double click and long press functions. Double-click the wifi reset button to enter smartconfig mode for wifi network configuration.

Temperature and humidity: using SHT71 temperature and humidity module

USB interface: It can provide power supply and communication. It adopts CH340E chip and can print system information for easy debugging.

Microcontroller: using STM32F103C8T6MCU

Relay: Using relay dedicated driver chip NUD3124LT1G, the circuit design is simple and reliable

WIFI module: Tuya’s WBR3 module

LED digital tube: real-time display of current temperature

Completion

PCB welding is completed, the temperature and humidity collection function is completed, and the TUYA module networking is completed;

It can be viewed in real time through the mobile phone APP or digital tube;
when the temperature is lower than the set value, the relay turns on the heater and heating can be carried out. When the set value is reached, the relay is turned off and the heating is stopped;
a one-click network distribution function is added, and the WIFI reset is performed by double-clicking the button. , enter smartconfig mode.

other instructions

The temperature and humidity printed by the serial port in the video only show the integer part and not the decimal part. The temperature and humidity displayed by the mobile APP were not recorded at the same time, so they look inconsistent.

When welding, pay attention to the CH340E and USB interface to prevent short circuit.

[Link to Tuya IoT development platform] https://auth.tuya.com/?from=https://www.tuya.com/cn/&_source=cbc30f99f7a6c4aebca6755c2fab437f (contains detailed development documents)