用Arduino UNO和4x4键盘制作MP3播放器 🎶🚀

4x4键盘通常被用来做门禁。看到我那个键盘放了很久吃灰，于是想给他赋予新的功能，这不它来了。播放mp3.

这里主控用的是Arduino UNO,
4x4键盘播放MP3图1

mp3模块

4x4键盘

喇叭一只。8欧即可

4x4键盘内部构造

这是连线图
[mw_shl_code=applescript,true]//you are free to copy the code,but please indicate the reference source is from the maker: gada888

#include <Keypad.h>
char myNum[4];
int i;
unsigned char order[4] = {0xAA,0x06,0x00,0xB0};

const byte ROWS = 4;
const byte COLS = 4;
char keys[ROWS][COLS] = {
{'1','2','3','A'},
{'4','5','6','B'},
{'7','8','9','C'},
{'*','0','#','D'}
};
byte rowPins[ROWS] = {9,8,7,6};
byte colPins[COLS] = {5,4,3,2};
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins,
ROWS, COLS);
void setup() {
Serial.begin(9600);
volume(0x1E);
}
void loop() {
Serial.println("Enter a num -");
  for ( i = 0; i < 4; ++i)
  {
while((myNum = keypad.getKey())==NO_KEY) {
   delay(1); // Just wait for a key
}
while(keypad.getKey() != NO_KEY) {
   delay(1);
}
  Serial.print(myNum);
  }
  if(myNum[3]=='A')
  {
play(0x01);
delay(500);
  }
  if(myNum[3]=='B')
  {
play(0x02);
delay(500);
i=0;
  }
  if(myNum[3]=='*')
  {
play(0x03);
delay(500);
i=0;
  }
  if(myNum[3]=='#')
  {
play(0x04);
delay(500);
i=0;
  }
  if(myNum[3]=='D')
  {
play(0x05);
delay(500);
i=0;
  }
}

void play(unsigned char Track)
{
unsigned char play[6] = {0xAA,0x07,0x02,0x00,Track,Track+0xB3};//0xB3=0xAA+0x07+0x02+0x00,鍗虫渶鍚庝竴浣嶄负鏍￠獙鍜?
Serial.write(play,6);
}
void volume( unsigned char vol)
{
unsigned char volume[5] = {0xAA,0x13,0x01,vol,vol+0xBE};//0xBE=0xAA+0x13+0x01,鍗虫渶鍚庝竴浣嶄负鏍￠獙鍜?
Serial.write(volume,5);
}
[/mw_shl_code]

最后，独一无二的键盘mp3完成了。按4下A，播放一首曲，按4下B播放另一首，我没有放很多曲子，因为mp3的模块仅仅8M存储。