introduction

This project made a small clock with ESP32. It can measure the temperature and humidity in real-time,displaying the current time and the future weather on screen. The temperature and humidity are measured through DHT11.The time is gotten by ntp server of aliyun.com while the future weather information is gotten from a website called Xinzhi Weather(心知天气).

Users can change the display picture by touching. Without touching,the picture will be display one by one for one second. When the temperature is too high,the buzzer will sing to remind user.

！正面图

！背面图

！显示效果图

Environment

IDE: Arduino 2.0

Hardware Requirement

MCU: ESP32 Dev Module

Modules:

• 543450 battery
• charging module
• touch module
• buzzer module (trigged by low voltage level)
• TFT display screen (communication in SPI)
• DHT11 (temperature and humidity module)

PCB/Bread Board

Some DuPont Lines

Module Introduction

DHT11 module is a integrated digital temperature and humidity sensor. The measurement range of temperature is from -20℃ to 60℃ while the range of humidity is from 5% to 95%.Besides,the accuracy of temperature is 2℃ while the accuracy of humidity is 5%.The reason why it is chosen in this project is its small volume and the convenience in development. The sensor has been calibrated in advance,so it can be used in project right away.

Refer to the datasheet of DHT11,we can find the timing sequence of reading data. If we want to read the data in DHT11,we should decease the voltage of data pin to low voltage for at least 18 ms and than the master device,ESP32,can read the voltage signal sent by the slave device,DHT11.