Audio Playback with HSC001 and ESP32

Introduction

Curious about audio playback in electronics? Let’s start with the HSC001 module—a compact, cost-effective 24-bit audio player with versatile applications like elevator music, device sound effects, and more. In this guide, we’ll explore how to configure and play audio files using the HSC001 with an ESP32 development board.

Components Needed

• HSC001 Serial Voice Module
• ESP32 Development Board
• Micro USB OTG Cable
• Jumper Wires

HSC001 Module Overview

The HSC001 is a playback chip supporting MP3/WAV formats, USB/SPI FLASH storage, and FAT16/FAT32 file systems. Key features:
- Simple serial command control
- Direct USB-to-SPI FLASH audio uploading
- 3W speaker output
- Low-voltage operation (3.3–5.4V)
- Reliable and user-friendly

Pin Configuration

The HSC001 has 10 pins:
1. SP+: Amplifier positive (3W max)
2. GND: Ground
3. VDD: Power input (3.3–5.4V)
4. SP-: Amplifier negative
5. MUTE: Mute control
6. DP: USB-DP
7. DM: USB-DM
8. ADK: ADK button
9. TX: UART output (3.3V TTL)
10. RX: UART input (3.3V TTL)

Audio Playback with ESP32

Hardware Setup

1. Power the HSC001 via ESP32’s 3.3V output.
2. Connect ESP32’s TX to HSC001’s RX (3.3V logic compatible).
3. Attach a speaker to SP+/SP-.
4. Insert a USB drive with audio files (named 0001.mp3, 0002.wav, etc.) into the HSC001.

Command Protocol

Commands follow this structure:
[0x7E] + [Len] + [CMD] + [Param1] + [Param2] + [0xEF]
- Len: Total bytes after Len (excluding start/end bytes).
- CMD: Play, pause, volume, etc.
- Params: Command-specific arguments.

Example: Play file 0001 → 7E 04 41 00 01 EF

ESP32 Code

Upload this code to cycle through audio files every 10 seconds:

byte currentSound = 0x01;  // Start with file 0001

void setup() {
  Serial.begin(9600);      // ESP32 UART1 (adjust pins if needed)
}

void loop() {
  // Send play command
  Serial.write(0x7E);
  Serial.write(0x04);      // Len = 4 (CMD + 2 params)
  Serial.write(0x41);      // CMD: Play by index
  Serial.write(0x00);      // Param1: High byte (00)
  Serial.write(currentSound); // Param2: Low byte (file number)
  Serial.write(0xEF);      // End byte

  delay(10000);            // Play for 10 seconds
  currentSound++;          // Next file
  if (currentSound > 10) currentSound = 1; // Reset after file 10
}

Code Breakdown

1. UART Initialization: ESP32 communicates at 9600 baud.
2. Command Structure:
3. 0x7E and 0xEF mark start/end.
4. 0x41 triggers playback by file index.
5. File Cycling: Increments currentSound every 10 seconds (adjust delay as needed).

Troubleshooting Tips

• Ensure audio files are named 0001, 0002, etc., and formatted as FAT32.
• Confirm wiring matches ESP32’s 3.3V logic (no level shifter needed).
• Check serial port configuration (e.g., use Serial1 if ESP32’s default UART is busy).