8×16 LED Dot Matrix Display Board – PH 2.54mm Connector with 4-Pin Dupont Cable (Red/Green/Yellow, 1.2mm Thickness)

Usage Guide

Hardware Overview

The 8×16 LED Dot Matrix Display Board consists of 128 LEDs arranged in 8 rows and 16 columns, driven by an onboard AIP1640 driver IC located on the back of the PCB. The module uses a 4-pin PH2.54 connector for easy connection to microcontrollers .

Component Identification:

• Front Side: 8×16 grid of LEDs (128 total)

• Back Side: AIP1640 driver chip

• Connector: 4-pin PH2.54 (2.54mm pitch)

• Mounting Holes: Four 2.2mm diameter holes at corners

Pinout Description

The 4-pin connector uses the following pinout (verify actual labeling on your module; common configurations include) :

Note: Pin ordering may vary by manufacturer. Please check the silkscreen labels on your specific module before wiring.

Wiring Instructions

Step 1 – Connect to Microcontroller

The module uses two-wire communication (similar to I2C). Below are common connections:

Arduino Uno/Nano Connection:

ESP32 Connection:

Raspberry Pi Connection:

micro:bit Connection (via expansion board):

Step 2 – Power Considerations

• A single module draws approximately 200mA maximum when all LEDs are illuminated at full brightness

• Most microcontroller 5V pins can supply sufficient current for one module

• For multiple modules or high-brightness applications, use an external 5V power supply (rated 1A or higher)

Software Setup

Important Communication Protocol Information:

The AIP1640 chip uses a two-wire interface that is I2C-like but may require specific initialization commands. Below is the general communication flow :

1. Start Condition: SCL high, SDA transitions from high to low

2. Command Setting: Send command to configure auto-address increment (typically 0x40)

3. Address Setting: Set starting address (typically 0xC0)

4. Data Transmission: Send 16 bytes of pattern data (one byte per column)

5. End Condition: SCL low, SDA low, then SCL high, SDA high

6. Display Control: Set brightness/pulse width (typically 0x8A for 4/16 duty cycle)

Arduino – Basic Display Example

This example uses direct I2C communication. For easier implementation, consider using a dedicated library (search for “AIP1640” or “LED Matrix” libraries in the Arduino Library Manager):

// 8x16 LED Dot Matrix Display with AIP1640 Driver
// Connections: SDA -> A4, SCL -> A5, VCC -> 5V, GND -> GND

#include <Wire.h>

#define SCL_PIN A5
#define SDA_PIN A4

// Smiley face pattern for 8x16 display (16 bytes)
// Each byte represents one column (8 pixels, MSB = top row)
unsigned char smiley[] = {
  0x00, 0x00, 0x1C, 0x02, 0x02, 0x02, 0x5C, 0x40,
  0x40, 0x5C, 0x02, 0x02, 0x02, 0x1C, 0x00, 0x00
};

void setup() {
  pinMode(SCL_PIN, OUTPUT);
  pinMode(SDA_PIN, OUTPUT);
  matrixDisplay(smiley);
}

void loop() {
  // Display stays on
}

void matrixDisplay(unsigned char *pattern) {
  // Start condition
  IIC_Start();
  // Command: Auto address increment (0x40)
  IIC_Send(0x40);
  IIC_End();
  
  // Start condition for data
  IIC_Start();
  // Set starting address to 0xC0
  IIC_Send(0xC0);
  // Send 16 bytes of pattern data
  for (int i = 0; i < 16; i++) {
    IIC_Send(pattern[i]);
  }
  IIC_End();
  
  // Set display brightness (0x8A = 4/16 duty cycle)
  IIC_Start();
  IIC_Send(0x8A);
  IIC_End();
}

void IIC_Start() {
  digitalWrite(SCL_PIN, HIGH);
  delayMicroseconds(3);
  digitalWrite(SDA_PIN, HIGH);
  delayMicroseconds(3);
  digitalWrite(SDA_PIN, LOW);
  delayMicroseconds(3);
}

void IIC_Send(unsigned char data) {
  for (int i = 0; i < 8; i++) {
    digitalWrite(SCL_PIN, LOW);
    delayMicroseconds(3);
    if (data & 0x01) {
      digitalWrite(SDA_PIN, HIGH);
    } else {
      digitalWrite(SDA_PIN, LOW);
    }
    delayMicroseconds(3);
    digitalWrite(SCL_PIN, HIGH);
    delayMicroseconds(3);
    data = data >> 1;
  }
}

void IIC_End() {
  digitalWrite(SCL_PIN, LOW);
  delayMicroseconds(3);
  digitalWrite(SDA_PIN, LOW);
  delayMicroseconds(3);
  digitalWrite(SCL_PIN, HIGH);
  delayMicroseconds(3);
  digitalWrite(SDA_PIN, HIGH);
  delayMicroseconds(3);
}

Creating Custom Patterns with a Modulo Tool:

To create your own patterns, use an online dot matrix modulo tool :

1. Search for “dot matrix modulo tool” or visit online pattern generators

2. Set matrix size to 8 (height) × 16 (width)

3. Click on cells to draw your pattern (left-click = ON, right-click = OFF)

4. Click “Generate” to obtain hexadecimal data (16 bytes)

5. Copy the generated array into your code

Important Note on Data Orientation: Depending on your module, the display may show patterns rotated 180 degrees or mirrored. If your pattern appears inverted, you may need to reverse the byte order or bit order. Test with a simple pattern (e.g., a single dot in the corner) to determine correct orientation .

Creating Custom Patterns

The 8×16 display uses 16 bytes of data (one byte per column). Each byte controls one column of 8 LEDs, where the Most Significant Bit (MSB) typically controls the top LED and the Least Significant Bit (LSB) controls the bottom LED .

Example: Heart Pattern for 8×16 Display

unsigned char heart[] = {
  0x00, 0x00, 0x00, 0x00, 0x00, 0x1C, 0x22, 0x42,
  0x84, 0x42, 0x22, 0x1C, 0x00, 0x00, 0x00, 0x00
};

Binary representation of heart pattern (columns 5-12):

• Column 5 (0x1C): 00011100 (fourth row from top)

• Column 6 (0x22): 00100010

• Column 7 (0x42): 01000010

• Column 8 (0x84): 10000100

• Column 9 (0x42): 01000010

• Column 10 (0x22): 00100010

• Column 11 (0x1C): 00011100

Multiple Module Cascading

Some versions of this module support cascading multiple units to create larger displays. To cascade:

1. Connect the output pins of the first module to the input pins of the second module

2. Match VCC, GND, SDA, and SCL

3. Address configuration may vary; check your specific module documentation

Installation Tips

• Mounting: Secure using M2.2 screws through the four corner mounting holes

• Ventilation: Ensure adequate airflow around the module, especially in high-brightness applications

• Cable Length: Keep I2C wires under 50cm to prevent signal degradation

• Pull-up Resistors: Some modules have onboard pull-up resistors for SDA and SCL; if not, add 4.7kΩ resistors to VCC

• Enclosure: For outdoor or dusty environments, protect the module in a weatherproof enclosure with a transparent window

• Multiple Modules: When using multiple I2C devices, ensure unique addresses or use an I2C multiplexer