Merge pull request #365 from standarddeviant/sdwav-pausable

AudioPlaySdWav Feature: togglePlayPause

examples/WavFilePlayerPause/WavFilePlayerPause.ino

+// Simple WAV file player example
+//
+// Three types of output may be used, by configuring the code below.
+//
+//   1: Digital I2S - Normally used with the audio shield:
+//         http://www.pjrc.com/store/teensy3_audio.html
+//
+//   2: Digital S/PDIF - Connect pin 22 to a S/PDIF transmitter
+//         https://www.oshpark.com/shared_projects/KcDBKHta
+//
+//   3: Analog DAC - Connect the DAC pin to an amplified speaker
+//         http://www.pjrc.com/teensy/gui/?info=AudioOutputAnalog
+//
+// To configure the output type, first uncomment one of the three
+// output objects.  If not using the audio shield, comment out
+// the sgtl5000_1 lines in setup(), so it does not wait forever
+// trying to configure the SGTL5000 codec chip.
+//
+// The SD card may connect to different pins, depending on the
+// hardware you are using.  Uncomment or configure the SD card
+// pins to match your hardware.
+//
+// Data files to put on your SD card can be downloaded here:
+//   http://www.pjrc.com/teensy/td_libs_AudioDataFiles.html
+//
+// This example code is in the public domain.
+
+#include <Audio.h>
+#include <Wire.h>
+#include <SPI.h>
+#include <SD.h>
+#include <SerialFlash.h>
+
+AudioPlaySdWav           playWav1;
+// Use one of these 3 output types: Digital I2S, Digital S/PDIF, or Analog DAC
+AudioOutputI2S           audioOutput;
+//AudioOutputSPDIF       audioOutput;
+//AudioOutputAnalog      audioOutput;
+AudioConnection          patchCord1(playWav1, 0, audioOutput, 0);
+AudioConnection          patchCord2(playWav1, 1, audioOutput, 1);
+AudioControlSGTL5000     sgtl5000_1;
+
+// Use these with the Teensy Audio Shield
+#define SDCARD_CS_PIN    10
+#define SDCARD_MOSI_PIN  7
+#define SDCARD_SCK_PIN   14
+
+// Use these with the Teensy 3.5 & 3.6 SD card
+//#define SDCARD_CS_PIN    BUILTIN_SDCARD
+//#define SDCARD_MOSI_PIN  11  // not actually used
+//#define SDCARD_SCK_PIN   13  // not actually used
+
+// Use these for the SD+Wiz820 or other adaptors
+//#define SDCARD_CS_PIN    4
+//#define SDCARD_MOSI_PIN  11
+//#define SDCARD_SCK_PIN   13
+
+void setup() {
+  Serial.begin(9600);
+
+  // Audio connections require memory to work.  For more
+  // detailed information, see the MemoryAndCpuUsage example
+  AudioMemory(8);
+
+  // Comment these out if not using the audio adaptor board.
+  // This may wait forever if the SDA & SCL pins lack
+  // pullup resistors
+  sgtl5000_1.enable();
+  sgtl5000_1.volume(0.5);
+
+  SPI.setMOSI(SDCARD_MOSI_PIN);
+  SPI.setSCK(SDCARD_SCK_PIN);
+  if (!(SD.begin(SDCARD_CS_PIN))) {
+    // stop here, but print a message repetitively
+    while (1) {
+      Serial.println("Unable to access the SD card");
+      delay(500);
+    }
+  }
+}
+
+void playFile(const char *filename)
+{
+  Serial.print("Playing file: ");
+  Serial.println(filename);
+
+  // Start playing the file.  This sketch continues to
+  // run while the file plays.
+  playWav1.play(filename);
+
+  // A brief delay for the library read WAV info
+  delay(5);
+
+  // Simply wait for the file to finish playing.
+  while (!playWav1.isStopped()) {
+    if(playWav1.isPlaying()) {
+      // play for 10 seconds
+      delay(10000);
+    }
+    else if(playWav1.isPaused()) {
+      // pause for 2 seconds
+      delay(2000);
+    }
+
+    // toggle play/pause state
+    playWav1.togglePlayPause();
+    Serial.println(filename);
+    Serial.print("positionMillis() = ");
+    Serial.println(playWav1.positionMillis());
+    Serial.print("lengthMillis()   = ");
+    Serial.println(playWav1.lengthMillis());
+    Serial.print("isPlaying() = ");
+    Serial.println(playWav1.isPlaying());
+    Serial.print("isPaused()  = ");
+    Serial.println(playWav1.isPaused());
+    Serial.print("isStopped() = ");
+    Serial.println(playWav1.isStopped());
+    Serial.println();
+  }
+}
+
+
+void loop() {
+  playFile("SDTEST1.WAV");  // filenames are always uppercase 8.3 format
+  delay(500);
+  playFile("SDTEST2.WAV");
+  delay(500);
+  playFile("SDTEST3.WAV");
+  delay(500);
+  playFile("SDTEST4.WAV");
+  delay(1500);
+}
+

play_sd_wav.cpp

 #define STATE_PARSE3			10 // looking for 8 byte data header
 #define STATE_PARSE4			11 // ignoring unknown chunk after "fmt "
 #define STATE_PARSE5			12 // ignoring unknown chunk before "fmt "
-#define STATE_STOP			13
+#define STATE_PAUSED			13
+#define STATE_STOP			14
 
 void AudioPlaySdWav::begin(void)
 {
 	if (irq) NVIC_ENABLE_IRQ(IRQ_SOFTWARE);
 }
 
+void AudioPlaySdWav::togglePlayPause(void) {
+	// take no action if wave header is not parsed OR
+	// state is explicitly STATE_STOP
+	if(state_play >= 8 || state == STATE_STOP) return;
+
+	// toggle back and forth between state_play and STATE_PAUSED
+	if(state == state_play) {
+		state = STATE_PAUSED;
+	}
+	else if(state == STATE_PAUSED) {
+		state = state_play;
+	}
+}
 
 void AudioPlaySdWav::update(void)
 {
 	int32_t n;
 
-	// only update if we're playing
-	if (state == STATE_STOP) return;
+	// only update if we're playing and not paused
+	if (state == STATE_STOP || state == STATE_PAUSED) return;
 
 	// allocate the audio blocks to transmit
 	block_left = allocate();
 	return (s < 8);
 }
 
+
+bool AudioPlaySdWav::isPaused(void)
+{
+	uint8_t s = *(volatile uint8_t *)&state;
+	return (s == STATE_PAUSED);
+}
+
+
+bool AudioPlaySdWav::isStopped(void)
+{
+	uint8_t s = *(volatile uint8_t *)&state;
+	return (s == STATE_STOP);
+}
+
+
 uint32_t AudioPlaySdWav::positionMillis(void)
 {
 	uint8_t s = *(volatile uint8_t *)&state;
-	if (s >= 8) return 0;
+	if (s >= 8 && s != STATE_PAUSED) return 0;
 	uint32_t tlength = *(volatile uint32_t *)&total_length;
 	uint32_t dlength = *(volatile uint32_t *)&data_length;
 	uint32_t offset = tlength - dlength;
 uint32_t AudioPlaySdWav::lengthMillis(void)
 {
 	uint8_t s = *(volatile uint8_t *)&state;
-	if (s >= 8) return 0;
+	if (s >= 8 && s != STATE_PAUSED) return 0;
 	uint32_t tlength = *(volatile uint32_t *)&total_length;
 	uint32_t b2m = *(volatile uint32_t *)&bytes2millis;
 	return ((uint64_t)tlength * b2m) >> 32;

play_sd_wav.h

 	AudioPlaySdWav(void) : AudioStream(0, NULL), block_left(NULL), block_right(NULL) { begin(); }
 	void begin(void);
 	bool play(const char *filename);
+	void togglePlayPause(void);
 	void stop(void);
 	bool isPlaying(void);
+	bool isPaused(void);
+	bool isStopped(void);
 	uint32_t positionMillis(void);
 	uint32_t lengthMillis(void);
 	virtual void update(void);