How to Use DF Player - HW-247A: Examples, Pinouts, and Specs

The DF Player - HW-247A is a compact and versatile MP3 player module designed for embedded systems and DIY projects. It can play audio files directly from a micro SD card and features a built-in amplifier, making it ideal for standalone audio playback. The module supports various audio formats, including MP3 and WAV, and can be controlled via serial communication, GPIO pins, or even standalone mode.

• Voice prompts and audio feedback in embedded systems
• DIY audio projects, such as jukeboxes or talking devices
• Alarm systems with pre-recorded messages
• Educational projects and interactive exhibits
• Portable audio playback systems

• Operating Voltage: 3.2V to 5.0V DC
• Current Consumption: 20mA (idle), up to 100mA (playback)
• Audio Formats Supported: MP3, WAV, WMA
• Storage: Micro SD card (up to 32GB, FAT16/FAT32 file system)
• Communication Interfaces: UART (9600 bps default), GPIO control
• Output:
  • Stereo audio output (DAC)
  • Mono speaker output (3W, 4Ω speaker supported)
• Dimensions: 22mm x 30mm x 11mm

The DF Player - HW-247A has 16 pins, but not all are required for basic operation. Below is the pinout:

1. Power Supply: Connect the VCC pin to a 3.2V-5.0V DC power source and GND to ground.
2. Audio Output:
   • For mono output, connect a 4Ω speaker to SPK_1 and SPK_2.
   • For stereo output, use DAC_R and DAC_L with an external amplifier or headphones.
3. Control Options:
   • UART Control: Connect RX and TX to a microcontroller (e.g., Arduino) for serial communication.
   • Standalone Mode: Use IO_1 and IO_2 pins to trigger specific audio files without a microcontroller.
4. Micro SD Card: Insert a formatted micro SD card with audio files into the module's slot. Ensure the files are named in a sequential format (e.g., 0001.mp3, 0002.mp3).

• Use a decoupling capacitor (e.g., 100µF) across the power supply pins to reduce noise.
• Ensure the micro SD card is formatted as FAT16 or FAT32 and does not exceed 32GB.
• Avoid connecting both the speaker output and DAC output simultaneously to prevent damage.
• Use a logic level shifter if interfacing with a 3.3V microcontroller to avoid damaging the module.

Below is an example of how to control the DF Player - HW-247A using an Arduino UNO:

• VCC: Connect to Arduino 5V.
• GND: Connect to Arduino GND.
• RX: Connect to Arduino digital pin 10 (via a 1kΩ resistor for protection).
• TX: Connect to Arduino digital pin 11.

#include "SoftwareSerial.h"

// Define RX and TX pins for SoftwareSerial
SoftwareSerial mySerial(10, 11); // RX = pin 10, TX = pin 11

void setup() {
  mySerial.begin(9600); // Initialize software serial at 9600 bps
  Serial.begin(9600);   // Initialize hardware serial for debugging

  Serial.println("Initializing DF Player...");
  delay(1000);

  // Send initialization command to DF Player
  mySerial.write(0x7E); // Start byte
  mySerial.write(0xFF); // Version
  mySerial.write(0x06); // Length
  mySerial.write(0x09); // Command: Select device
  mySerial.write(0x00); // Feedback
  mySerial.write(0x02); // Parameter 1: SD card
  mySerial.write(0x00); // Parameter 2
  mySerial.write(0xFE); // Checksum (high byte)
  mySerial.write(0xED); // Checksum (low byte)
  mySerial.write(0xEF); // End byte

  Serial.println("DF Player initialized.");
}

void loop() {
  // Example: Play the first audio file (0001.mp3)
  Serial.println("Playing track 1...");
  mySerial.write(0x7E); // Start byte
  mySerial.write(0xFF); // Version
  mySerial.write(0x06); // Length
  mySerial.write(0x03); // Command: Play track
  mySerial.write(0x00); // Feedback
  mySerial.write(0x00); // Parameter 1: High byte of track number
  mySerial.write(0x01); // Parameter 2: Low byte of track number
  mySerial.write(0xFE); // Checksum (high byte)
  mySerial.write(0xF7); // Checksum (low byte)
  mySerial.write(0xEF); // End byte

  delay(5000); // Wait for 5 seconds before repeating
}

1. No Sound Output:

   • Ensure the speaker is properly connected to SPK_1 and SPK_2.
   • Verify that the audio file format is supported (e.g., MP3 or WAV).
   • Check the micro SD card for proper formatting (FAT16/FAT32) and file naming.

2. Module Not Responding to Commands:

   • Confirm the RX and TX connections are correct and not swapped.
   • Use a 1kΩ resistor on the RX line to protect the module.
   • Ensure the baud rate is set to 9600 bps in your code.

3. Playback Stops Abruptly:

   • Check the power supply for stability and ensure sufficient current is available.
   • Verify the micro SD card is not corrupted or damaged.

• Can I use a 3.3V microcontroller with the DF Player? Yes, but use a logic level shifter on the RX pin to avoid damaging the module.

• What is the maximum speaker power supported? The module supports up to 3W speakers with a 4Ω impedance.

• Can I play audio files in a specific folder? Yes, but you need to use folder-specific commands via UART. Refer to the module's datasheet for details.