### Project 1: Hello World

**Overview**

For ESP32 beginners, we will start with some simple things. In this project, you only need a ESP32 mainboard, a USB cable and a computer to complete the "Hello World\!" project, which is a test of communication between the ESP32 mainboard and the computer as well as a primary project.

**Components**

| ![image-20231113151026574](media/image-20231113151026574.png) | ![image-20231113151032312](media/image-20231113151032312.png) |
| ------------------------------------------------------------ | ------------------------------------------------------------ |
| ESP32*1                                                      | USB Cable*1                                                  |


**Wiring Diagram：**

In this project, we will use a USB cable to connect the ESP32 to a computer.

![image-20231020082805460](media/image-20231020082805460.png)

**Test Code**


```c
//*************************************************************************************
/*
 * Filename    : Hello World
 * Description : Enter the letter R,and the serial port displays"Hello World".
 * Auther      :http//www.keyestudio.com
*/
char val;// defines variable "val"
void setup()
{
Serial.begin(9600);// sets baudrate to 9600
}
void loop()
{
  if (Serial.available() > 0) {
    val=Serial.read();// reads symbols assigns to "val"
    if(val=='R')// checks input for the letter "R"
    {  // if so,    
     Serial.println("Hello World!");// shows “Hello World !”.
    }
  }
}
//*************************************************************************************
```

Before uploading the test code to the ESP32，click“Tools”→“Board”，select“ESP32 Wrover Module”.

![](media/fa56991b6368d175880603c446b81e2a.png)

Select the correct serial port.

![](media/1318a740375ee46c2bb9ec72bad3aeb7.png)

Note：For macOS users, if the upload fails, set the baud rate to 115200 before clicking ![](media/b0d41283bf5ae66d2d5ab45db15331ba.png).

![](media/97f4ac2f7d2aac69f5b5cd558668b307.png)

Click ![](media/b0d41283bf5ae66d2d5ab45db15331ba.png)to upload the test code to the ESP32.

![](media/6e6ae41d4b07591efcb3c907958aa719.png)

Note: If the uploading code fails, you can press and hold the Boot button on the ESP32 after clicking![](media/d09c4a31563f04a42d451e7bc1a5fb8a.png)and release it after the percentage of uploading progress appears.![](media/dc77bfcf5851c8f43aab6cbe7cec7920.png), as shown below:  

![](media/157ee2e7687559d9812d24edec758150.png)

The code is uploaded successfully.

![](media/3511be64175bc28c8ab8a4a3b766e5c3.png)

**Test Result**

After uploading successfully，we will use a USB cable to power on，click![](media/2f6bca56f724e45a855335cb53ae9b4e.png) to enter the serial monitor and set the baud rate to 9600，enter the letter“R”，click“Send”，then the serial monitor prints“Hello World\!”.

![](media/cc9f1801ab1db618316fea36c8d9ed3b.png)