Error with Sparkfun MP3 Shield and Arduino Due playing music files

Question

The code worked on my Ardino Uno. I plugged it up the exact same way and am now getting an error.

Here is the error I get when I try to upload my code to the due:

Arduino: 1.8.5 (Windows 10), Board: "Arduino Due (Programming Port)"

C:\Program Files (x86)\Arduino\libraries\SFEMP3Shield\SFEMP3Shield.cpp: In static member function 'static void SFEMP3Shield::refill()':

C:\Program Files (x86)\Arduino\libraries\SFEMP3Shield\SFEMP3Shield.cpp:1984:7: error: 'sei' was not declared in this scope

   sei();

       ^

C:\Program Files (x86)\Arduino\libraries\SFEMP3Shield\SFEMP3Shield.cpp:2006:9: error: 'cli' was not declared in this scope

     cli(); // allow transfer to occur with out interruption.

         ^

C:\Program Files (x86)\Arduino\libraries\SFEMP3Shield\SFEMP3Shield.cpp: In member function 'void SFEMP3Shield::SendSingleMIDInote()':

C:\Program Files (x86)\Arduino\libraries\SFEMP3Shield\SFEMP3Shield.cpp:2053:7: error: 'cli' was not declared in this scope

   cli(); // allow transfer to occur with out interruption.

       ^

C:\Program Files (x86)\Arduino\libraries\SFEMP3Shield\SFEMP3Shield.cpp:2067:7: error: 'sei' was not declared in this scope

   sei();  // renable interrupts for other processes

       ^

exit status 1
Error compiling for board Arduino Due (Programming Port).

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Here is my code:

#include <SPI.h>
#include <SdFat.h>
#include <SdFatUtil.h>
#include <SFEMP3Shield.h>


SdFat sd;
SFEMP3Shield MP3player;

const uint8_t volume = 10; // MP3 Player volume 0=max, 255=lowest (off)
//10 for normal 50 for testing

const uint16_t monoMode = 1;

void setup() {
  initSD();
  initMP3Player();
}

void loop() {
  if(!MP3player.isPlaying()){
    MP3player.playTrack(1);
  }
}

void initSD() {
  if(!sd.begin(SD_SEL, SPI_HALF_SPEED)) 
    sd.initErrorHalt();
  if(!sd.chdir("/")) 
    sd.errorHalt("sd.chdir");
}

void initMP3Player() {
  uint8_t result = MP3player.begin();
  MP3player.setVolume(volume, volume);
  MP3player.setMonoMode(monoMode);
}

Answer 1

The library is written for the Uno, not the Due. It relies on two instructions that are only available in the AVR compiler.

Newer versions of the core provide a pair of macros, interrupts() and noInterrupts() that should be used in place of sei() and cli() respectively, which should be provided by the Due's core as well to make it cross-platform. However that library has never been updated to work with those macros.

You could replace the sei() and cli() calls in the library with interrupts() and noInterrupts(), however that may not make it work, since it was written with the Uno and other AVR based chips in mind.