Pinout — WCMCU-5102 module

Pin	Signal	Description
`XMT`	enable	PCM5102A mute control input; hold high for normal output, low to mute.
`FMT`	digital	Audio data format select input for the DAC's I2S-compatible interface.
`LRCK`	clock	I2S left/right word clock input selecting the active stereo channel.
`DIN`	data	I2S serial audio data input from the MCU or audio source.
`BCK`	clock	I2S bit clock input used to clock serial audio data into the DAC.
`SCL`	clock	DAC system clock input if used; many PCM5102A modules can derive clock from BCK.
`DMP`	digital	De-emphasis control input for PCM5102A audio filtering.
`FLT`	digital	Digital filter select input for PCM5102A DAC response mode.
`GND`	ground	Ground reference for power and I2S logic signals.
`3.3V`	power	3.3 V supply rail for DAC logic; use with compatible 3.3 V systems.
`VCC`	power	Main power input for the DAC module, typically from 3.3 V or 5 V.
`L`	analog	Left analog line-level audio output; feed an amplifier input, not a speaker directly.
`GND.1`	ground	Analog audio ground for the line-out L/R outputs and amplifier input reference.
`R`	analog	Right analog line-level audio output; feed an amplifier input, not a speaker directly.

Wiring notes

This is a LINE-LEVEL DAC — its output (Line-out pads and 3.5mm jack) is NOT amplified. It can drive headphones or an external amplifier, but it CANNOT drive a speaker directly. To connect a speaker, you MUST place an audio amplifier between this module and the speaker (e.g. PAM8403 for stereo, MAX98357A for I2S mono, or LM386). Connect the Line-out LEFT/RIGHT/GND pads to the amplifier input, then connect the amplifier output to the speaker.

Example wiring diagram — WCMCU-5102 module

From	To	Wire
`board:5V`	`x1:VCC`	red
`board:GND`	`x1:GND`	black
`board:D9`	`x1:XMT`	green
`board:D8`	`x1:FMT`	blue
`board:D13`	`x1:LRCK`	yellow
`board:D11`	`x1:DIN`	purple
`board:D12`	`x1:BCK`	cyan
`board:D7`	`x1:SCL`	magenta
`board:D6`	`x1:DMP`	brown
`board:D5`	`x1:FLT`	pink
`x1:L`	`board:A0`	teal
`x1:GND.1`	`board:GND.1`	black
`x1:R`	`board:A1`	lime

Example Arduino code — WCMCU-5102 module

This example was written and compile-checked for the arduino-uno. Codey Online adapts it to any other supported board for you.

// Canonical beginner example for the WCMCU-5102 module on Arduino Uno
// This sketch does not use an I2S library so it compiles on the default AVR core.
// It demonstrates basic control of the module's mode pins and confirms the board is running.
// IMPORTANT: The module output is line-level only. Do NOT connect a speaker directly.

#include <Arduino.h>

// Wiring used in this example:
// VCC  -> 5V
// GND  -> GND
// XMT  -> D9
// FMT  -> D8
// SCL  -> D7
// DMP  -> D6
// FLT  -> D5
// L    -> A0 (monitoring only; optional, not read in this sketch)
// R    -> A1 (monitoring only; optional, not read in this sketch)

const int ENABLE_PIN = 9;
const int FMT_PIN = 8;
const int SCL_PIN = 7;
const int DMP_PIN = 6;
const int FLT_PIN = 5;

void setup() {
  Serial.begin(115200);

  pinMode(ENABLE_PIN, OUTPUT);
  pinMode(FMT_PIN, OUTPUT);
  pinMode(SCL_PIN, OUTPUT);
  pinMode(DMP_PIN, OUTPUT);
  pinMode(FLT_PIN, OUTPUT);

  // Enable normal audio output.
  digitalWrite(ENABLE_PIN, HIGH);

  // Typical PCM5102A-friendly control settings.
  digitalWrite(FMT_PIN, LOW);
  digitalWrite(SCL_PIN, LOW);
  digitalWrite(DMP_PIN, LOW);
  digitalWrite(FLT_PIN, LOW);

  Serial.println("WCMCU-5102 module example");
  Serial.println("Control pins set: XMT=HIGH, FMT=LOW, SCL=LOW, DMP=LOW, FLT=LOW");
  Serial.println("This example demonstrates wiring and power-up only.");
  Serial.println("Connect L/R to an external amplifier or headphones, not a speaker directly.");
}

void loop() {
  // Blink the enable pin very briefly once per second as a simple visible test.
  // The DAC stays enabled most of the time.
  digitalWrite(ENABLE_PIN, LOW);
  delay(10);
  digitalWrite(ENABLE_PIN, HIGH);

  Serial.println("Module control pins are active.");
  delay(990);
}