code for speaker

Author: ixaxaar

src/mic.cpp

@@ -32,7 +32,7 @@ MicManager::MicManager(int bckPin,
   I2SStream i2sStream;
   cfg = i2sStream.defaultConfig(RX_MODE);
 
-  cfg.i2s_format = I2S_STD_FORMAT; // optional because default setting
+  cfg.i2s_format = I2S_STD_FORMAT;
   cfg.bits_per_sample = BITS_PER_SAMPLE;
   cfg.channels = CHANNELS;
   cfg.sample_rate = SAMPLE_RATE;
@@ -56,7 +56,9 @@ MicManager::startRecording(String fileName)
 
   file = SD.open(fileName, FILE_WRITE);
   file.seek(0);
+
   copier.setCheckAvailableForWrite(false);
+
   i2sStream.begin(cfg);
   copier.begin(file, i2sStream);
 }

src/mic.h

@@ -19,8 +19,8 @@ class MicManager
                       int sdMOSIPin,
                       int sdCLKPin);
   void startRecording(String fileName);
-  void stopRecording();
   void record();
+  void stopRecording();
 
 private:
   int mic_BCK, mic_WS, mic_DATA;

src/speaker.cpp

@@ -1 +1,46 @@
 #include "speaker.h"
+
+#define SAMPLE_RATE 16000
+#define CHANNELS 1
+#define BITS_PER_SAMPLE 32
+
+// Source: SD card over i2c
+SPIClass sd_spi;
+File file;
+
+// Destination: PCM out via one wire to AMP -> speakers
+#define PIN_AMP_LEFT_CHANNEL 10
+#define PIN_AMP_RIGHT_CHANNEL 11
+
+Speaker::Speaker(int sdCSPin, int sdMISOPin, int sdMOSIPin, int sdCLKPin)
+  : sd_CS(sdCSPin)
+  , sd_MISO(sdMISOPin)
+  , sd_MOSI(sdMOSIPin)
+  , sd_CLK(sdCLKPin)
+{
+  sd_spi.begin(sdCLKPin, sdMISOPin, sdMOSIPin, sdCSPin);
+}
+
+void
+Speaker::play(String fileName)
+{
+  if (!SD.begin(sd_CS, sd_spi)) {
+    printf("SD card failed to initialize");
+    return;
+  }
+
+  file = SD.open(fileName, FILE_READ);
+
+  size_t bytesRead = 1;
+  uint8_t buffer[SAMPLE_RATE];
+
+  while (bytesRead > 0) {
+    bytesRead = file.read(buffer, sizeof(buffer));
+
+    for (size_t i = 0; i < bytesRead; i++) {
+      dacWrite(PIN_AMP_LEFT_CHANNEL, buffer[i]);
+      dacWrite(PIN_AMP_RIGHT_CHANNEL, buffer[i]);
+      delayMicroseconds(1000000 / SAMPLE_RATE);
+    }
+  }
+}

src/speaker.h

@@ -0,0 +1,19 @@
+// speaker.h
+#ifndef SPEAKER_H
+#define SPEAKER_H
+
+#include "AudioLibs/AudioSourceSD.h"
+#include "AudioTools.h"
+
+class Speaker
+{
+public:
+  Speaker(int sdCSPin, int sdMISOPin, int sdMOSIPin, int sdCLKPin);
+
+  void play(String fileName);
+
+private:
+  int sd_CS, sd_MISO, sd_MOSI, sd_CLK;
+};
+
+#endif // SPEAKER_H