Jiří Sklenář - DFmini MP3 player

#include <SoftwareSerial.h>
#define RX_PIN 8
#define TX_PIN 9

SoftwareSerial mySerial(RX_PIN, TX_PIN);

void setup() {
  mySerial.begin(9600);

  sendMP3cmd(0x0C,0x00);  // reset mp3 modulu
  _delay_ms(50);
  sendMP3cmd(0x09,0x02);  // soubory jsou na SD karte
  _delay_ms(20);
  sendMP3cmd(0x06,0x1F);  // nastav hlasitost
  _delay_ms(20);

  sendMP3cmd(0x03,0x01);  // prehraj 1 skladbu
}

void loop() {
  // nic ....

}


void sendMP3cmd(uint8_t cmd, uint16_t par)      // tvorba prikazu pro mp3 prehravac - netreba popisu - viz datasheet
{
  //                          CMD  ACK   MSB   LSB   CMSB  LMSB  EOF
  uint8_t command[] = {0x7E, 0xFF, 0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xEF}; // buffer
  command[3]=cmd;
  command[5]=(uint8_t)(par>>8);
  command[6]=(uint8_t)(par & 0x00ff);
  uint16_t crc=0x0000;
  for (uint8_t a=1; a <=6 ; a++) crc-=command[a];
  command[7]=(uint8_t)(crc>>8);
  command[8]=(uint8_t)(crc & 0x00ff);
  for (uint8_t a=0; a<10; a++) mySerial.write(command[a]);
}