How to Use Nextion Touch LCD 2.4": Examples, Pinouts, and Specs

The Nextion Touch LCD 2.4" is an intelligent Human Machine Interface (HMI) solution that provides a control and visualization interface between a human and a process, machine, application, or appliance. It is a standalone device that includes an onboard processor and memory for the creation of custom user interfaces. Common applications include IoT devices, DIY electronics projects, industrial controls, and consumer electronics.

• Display Size: 2.4 inches
• Resolution: 320 x 240 pixels
• Color: 65K true colors
• Touch Type: Resistive touch
• Interface: UART (Serial)
• Onboard MCU: 32-bit ARM Cortex-M0
• Flash Memory: 4MB
• RAM: 3584 bytes
• Power Supply: 5V DC / 500mA
• Operating Temperature: -20°C to +70°C

1. Power Supply: Connect the +5V and GND pins to a stable 5V power source.
2. Serial Communication: Connect the TX and RX pins to a microcontroller or other UART interface. Ensure that the TX pin of the Nextion is connected to the RX pin of the microcontroller and vice versa.
3. Programming: Use the Nextion Editor to design the user interface and upload it to the Nextion LCD via a micro USB cable.

• Always disconnect the power before making or changing connections.
• Use a logic level converter if the microcontroller operates at a different voltage level than the Nextion display.
• Avoid static discharge by grounding yourself before handling the display.
• Ensure that the power supply can provide sufficient current for both the display and the microcontroller.

#include <SoftwareSerial.h>

// Define the Nextion RX and TX pins
#define NEXTION_RX 10
#define NEXTION_TX 11

// Initialize the Nextion display
SoftwareSerial nextion(NEXTION_RX, NEXTION_TX);

void setup() {
  // Set the baud rate for the Nextion display and the Arduino serial monitor
  nextion.begin(9600);
  Serial.begin(9600);
}

void loop() {
  // Check if data is available to read from the Nextion display
  if (nextion.available()) {
    String message = nextion.readString();
    Serial.print("Message from Nextion: ");
    Serial.println(message);
  }

  // Check if data is available to read from the serial monitor
  if (Serial.available()) {
    String command = Serial.readString();
    nextion.print(command);
  }
}

• Display Not Responding: Ensure that the power supply is connected correctly and providing the right voltage. Check the serial connections between the Nextion display and the microcontroller.
• Garbled Data on Screen: Verify that the baud rate of the Nextion display matches the baud rate set in the microcontroller code.
• Touch Not Working: Make sure the touch panel is properly calibrated using the Nextion Editor.

Q: Can I use the Nextion display with a 3.3V microcontroller? A: Yes, but a logic level converter is recommended to match the voltage levels for reliable communication.

Q: How do I update the user interface on the Nextion display? A: Use the Nextion Editor to create or modify the user interface and upload it to the display via a micro USB cable.

Q: What is the maximum length for serial communication cables? A: It is recommended to keep the cable length as short as possible, ideally less than 2 meters, to prevent signal degradation.

For further assistance, consult the Nextion community forums or contact technical support.