Working with Arduino

This chapter contains the following sections. Please read as needed:

• Arduino Getting Started
• Setting Up Development Environment
• Demo

Arduino Getting Started

New to Arduino ESP32 development and looking for a quick start? We have prepared a comprehensive Getting Started Tutorial for you.

• Section 0: Getting to Know ESP32
• Section 1: Installing and Configuring Arduino IDE
• Section 2: Arduino Basics
• Section 3: Digital Output/Input
• Section 4: Analog Input
• Section 5: Pulse Width Modulation (PWM)
• Section 6: Serial Communication (UART)
• Section 7: I2C Communication
• Section 8: SPI Communication
• Section 9: Wi-Fi Basics
• Section 10: Web Server
• Section 11: Bluetooth
• Section 12: LVGL GUI Development
• Section 13: Comprehensive Project

Note: This tutorial uses the ESP32-S3-Zero as a reference example, and all hardware code is based on its pinout. Before you start, we recommend checking the pinout of your development board to ensure the pin configuration is correct.

Setting Up Development Environment

1. Installing and Configuring Arduino IDE

Please refer to the tutorial Installing and Configuring Arduino IDE to download and install the Arduino IDE and add ESP32 support.

2. Installing Libraries

• When installing Arduino libraries, there are typically two methods: Install Online and Install Offline. If the library installation requires Install Offline, you must use the provided library file.
• For most libraries, users can easily search for and install them via the Arduino IDE's online Library Manager. However, some open-source or custom libraries are not synchronized to the Arduino Library Manager and therefore cannot be found through online search. In this case, users can only install these libraries manually via offline methods. You can click this link to download the demo package for the ESP32-S3-LCD-2.8 board from the Arduino directory. The Arduino\libraries directory within this package contains all the necessary library files required for this tutorial.

Library/File Name	Description	Version	Installation Method
LVGL	Graphics Library	v8.3.10	"Install Offline"
ESP32-audioI2S-master	Audio Decoding Library	v2.0.0	"Install Offline"

Version Compatibility Notes

There are strong dependencies between versions of LVGL and its driver libraries. For example, a driver written for LVGL v8 may not be compatible with LVGL v9. To ensure that the examples can be reproduced reliably, it is recommended to use the specific versions listed in the table above. Mixing different versions of libraries may lead to compilation failures or runtime errors.

Installation Steps:

1. Download the demo package.

2. Copy all the folders (e.g., LVGL, ESP32-audioI2S-master) from its Arduino\libraries directory to your Arduino libraries folder.

   info

   The path to the Arduino libraries folder is typically: c:\Users\<username>\Documents\Arduino\libraries.

   You can also locate it in the Arduino IDE by going to File > Preferences and checking the "Sketchbook location". The libraries folder is the libraries subfolder within this path.

3. For other installation methods, please refer to: Arduino Library Management Tutorial.

Required Board Installation Instructions for ESP32-S3-LCD-2.8

Board Name	Installation Requirement	Version Requirement
ESP32 by Espressif Systems	"Install Offline" / "Install Online”	≥3.0.0

Demo

The Arduino demos are located in the Arduino directory of the demo package.

01_LVGL_Arduino

Demo Description

• This example demonstrates how to integrate the LVGL graphics library on an embedded device. By coordinating hardware initialization and graphics library initialization, a complete graphical interface runtime environment is built. Continuously calling the LVGL core loop ensures that the graphical interface responds to user interactions and refreshes system status in real time while properly managing CPU resource usage.

Hardware Connection

• Insert the TF card into the development board
• Connect the board to the computer
  

Code Analysis

• setup():

  • Initializes multiple hardware modules, including flash test, power, battery, I2C bus, real-time clock, gyroscope, backlight, TF card, audio, and display. This ensures that each hardware component works properly and provides necessary functional support for the system.
  • Initializes LVGL to prepare for graphical interface display and interaction.
  • Optionally calls different LVGL examples or specific functions to demonstrate various graphical effects and interaction methods.

• loop():

  • Continuously calls Lvgl_Loop to ensure that the LVGL graphical interface is constantly updated, responds to user interactions, and reflects system status changes.
  • Adds a short delay to avoid excessive CPU usage while allowing the system time to process other tasks or wait for external events.

Operation Result

• LCD screen display:

• Parameter description:

Parameter	Function	Description
SD Card	Displays the TF card size	Connect a TF card. If recognition fails, please format the TF card to FAT32 (if initial recognition fails, wait a moment and then reset to check again)
Flash Size	Displays the Flash size	Onboard 16MB Flash
Battery Voltage	Battery voltage	Battery voltage can be detected when a battery is connected
Angular deflection	Displays the board's angular deviation	Displays deviation in three directions
RTC Time	Displays RTC time	The RTC time may not match the current time because data cannot be retained when power is off. To keep the RTC time accurate, you need to connect an RTC battery and update the RTC time
Wireless scan	Displays the number of Wi-Fi networks scanned	Scan ends with "Scan Finish" at the end
Backlight brightness	Brightness slider	Adjusts screen brightness