Reference

AD Button Controlling

Control by Button

1. Tap the PLAY button to play or pause(Blue LED keeps on when playing and blinks slowly when pausing).
   
2. Long-press the for 2 seconds to switch to the next song(Blue LED blinks twice when switching).

Get AD Button from DFRobot Store or DFRobot Distributor.

Communication Protocol Description

AT Command Controlling

Note:

1. "\r\n is" omitted in all the commands below, and you need to add it to the end of the command in actual use. For example "AT+VOL=5\r\n", designate volume to "5".
   
2. Default serial baud rate: 115200

/**
 * @brief Test Connection
 */
AT  //Test Connection

/**
 * @brief Set/Query Volume（Volume：0-30）(Power-down save) 
 * @param -n:Volume -n
 *        +n:Volume +n
 *         n:Designate volume to n
 *         ?:Query volume
 */
AT+VOL=-5  //Volume -5

AT+VOL=?   //Query volume
return：VOL = [10]   //The current volume is 10

/**
 * @brief Control playback mode
 * @param  1:repeat one song
 *         2:repeat all
 *         3:play one song and pause
 *         4:Play randomly
 *         5:Repeat all in the folder
 *         ?:query the current playback mode
 */
AT+PLAYMODE=1   //Switch to repeat-one-song mode 

AT+PLAYMODE=?   //Query current playback mode 
Return：PLAYMODE =1  //Current playback mode: repeat one song

/**
 * @brief Control playing
 * @param    PP:Play & Pause
 *         NEXT:next
 *         LAST:last
 */
AT+PLAY=NEXT   //last

/**
 * @brief Playing time control 
 * @param -n:Fast Rewind n S
 *        +n:Fast Forward n S
 *         n:Start playing from the Nth second
 */
AT+TIME=-5   //Fast Rewind 5S

/**
 * @brief Query playback information 
 * @param  1:Query the file number of the currently-playing file
 *         2:Query the total number of the files
 *         3:Query the time length the song has played
 *         4:Query the total time of the currently-playing file
 *         5:Query the file name of the currently-playing file
 */
AT+QUERY=1   //Query the file number of the currently-playing file

AT+QUERY=5  //Query the file name of the currently-playing file
Return：test.mp3    //The currently-playing file is "test.mp3"


/**
 * @brief Play the file of the specified number 
 * @param        n:File number(Play the first file if there is no such file)
 */
AT+PLAYNUM=5                       //Play file No. 5 

/**
 * @brief Play the specific file
 * @param File path
 */
AT+PLAYFILE=/DF_REC/test.MP3        //Play the test.mp3 under DF_REC once 

/**
 * @brief Amplifier On/OFF command
 * @param    ON, OFF
 */
AT+AMP=ON   //Turn on amplifier 

/**
 * @brief Delete currently-playing file
 */
AT+DEL

/**
 * @brief Set baud rate (power-down save, valid after re-powering on)
 * @param    9600、19200、38400、57600、115200
 */
AT+BAUDRATE=115200  //Set baud rate to 115200

/**
 * @brief Prompt tone ON/OFF command (Power-down save)
 * @param    ON, OFF
 */
AT+PROMPT=ON   //Turn on prompt tone 

//LED Prompt On/Off Command(Power-down save) 
/**
 * @brief LED Prompt ON/OFF command (Power-down save)
 * @param    ON, OFF
 */
AT+LED=ON   //Turn on LED Prompt 

API Description

• Main API Function List

  /**
   * @brief Set volume 
   * @param vol:0-30
   * @return true or false
   */
  bool setVol(uint8_t vol);
  
  /**
   * @brief Set playback mode 
   * @param ePlayMode_t:SINGLECYCLE,ALLCYCLE,SINGLE,RANDOM,FOLDER
   * @return true or false
   */
  bool setPlayMode(ePlayMode_t mode);
  
  /**
   * @brief Play 
   * @return true or false
   */
  bool start();
  
  /**
   * @brief Pause 
   * @return true or false
   */
  bool pause();
  
  /**
   * @brief Next 
   * @return true or false
   */
  bool next();
  
  /**
   * @brief Previous 
   * @return true or false
   */
  bool last();
  
  /**
   * @brief Fast forward the currently-playing song
   * @param second  FF time(Unit: S) 
   */
  bool fastForward(uint16_t second);
  
  /**
   * @brief Fast Rewind the currently-playing song 
   * @param second  FR time(Unit: S)
   */
  bool fastReverse(uint16_t second);
  
  /**
   * @brief Let the currently-playing song start playing from a particular point of the audio file 
   * @param second  Fixed time point
   */
  bool setPlayTime(uint16_t second);
  
  /**
   * @brief Get file number 
   */
  uint16_t getCurFileNumber();
  
  /**
   * @brief Get the number of files available to play 
   */
  uint16_t getTotalFile();
  
  /**
   * @brief Get the time length the current song has played 
   */
  uint16_t getCurTime();
  
  /**
   * @brief Get the total length of the currently-playing song
   */
  uint16_t getTotalTime();
  
  /**
   * @brief Get the name of the playing file 
   */
  String   getFileName();
  
  /**
   * @brief Play file of the specific path 
   * @param The designated path 
   */
  bool playSpecFile(String str);
  
  /**
   * @brief Play the file of specific number, the numbers are arranged according to the sequences the files copied into the U-disk 
   * @param File number, can be obtained by getCurFileNumber()
   */
  bool playFileNum(int16_t num);
  
  /**
   * @brief Delete the currently-playing file 
   * @return true or false
   */
  bool delCurFile();