proton

MusicPlayer.cpp

 1#include <Arduino.h>
 2#include <SPI.h>
 3#include <Adafruit_VS1053.h>
 4#include <SD.h>
 5#include "MusicPlayer.h"
 6
 7
 8
 9MusicPlayer::MusicPlayer(int8_t cs, int8_t dcs, int8_t dreq, int8_t cardcs)
10{
11  musicPlayer = new Adafruit_VS1053_FilePlayer(cs, dcs, dreq, cardcs);
12  musicPlayer->begin();
13  musicPlayer->setVolume(1, 1); // lower = louder
14  musicPlayer->sineTest(0x44, 500);
15  SD.begin(cardcs);
16}
17
18void
19MusicPlayer::setVolume(uint8_t left, uint8_t right)
20{
21  musicPlayer->setVolume(left, right);
22}
23
24
25boolean
26MusicPlayer::startPlayingFile(const char *trackname)
27{
28  return musicPlayer->startPlayingFile(trackname);
29}
30
31boolean
32MusicPlayer::isPlaying()
33{
34  return musicPlayer->playingMusic;
35}
36
37void
38MusicPlayer::stopPlaying()
39{
40  musicPlayer->stopPlaying();
41}
42
43void
44MusicPlayer::poll(unsigned long jiffies)
45{
46  /* Cleverness ensues
47   * 
48   * The Adafruit library is written to let you go off and do whatever you need,
49   * hooking into an interrupt to sort of act like a multitasking operating system,
50   * interrupting your program periodically.
51   * 
52   * That's smart, since it makes it easy to use,
53   * but we want this to be responsive, and can't handle something barging in and taking up lots of time:
54   * it makes things look really uneven as our display code pauses to fill the buffer.
55   * Fortunately, we don't have to fill the entire buffer at once, we can trickle data in.
56   * That's what this does. 
57   * 
58   * Since the entire program is polling, without ever calling delay,
59   * and hopefully doing what needs to be done quickly,
60   * we check to see if the music chip wants more data.
61   * If it does, we give it one chunk, and only one chunk,
62   * rather than filling its buffer back up completely.
63   * 
64   * There is still some weirdness with this loop,
65   * possibly because the SPI routines are masking interrupts used to increment millis.
66   * But it's remarkably more fluid than the other way.
67   */
68  
69  if (musicPlayer->playingMusic && musicPlayer->readyForData()) {
70    int bytesread = musicPlayer->currentTrack.read(musicPlayer->mp3buffer, VS1053_DATABUFFERLEN);
71    if (bytesread == 0) {
72      musicPlayer->playingMusic = false;
73      musicPlayer->currentTrack.close();
74    } else {
75      musicPlayer->playData(musicPlayer->mp3buffer, bytesread);
76    }
77  }
78}