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libraries/audio-tools/examples/sandbox/spi/spi-master/spi-master.ino

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+
+/**
+ * We use the default Arduino SPI API to send/write the data as SPI Master.
+ * For a sample rate of 44100 with 2 channels and 16 bit data you need to be
+ * able to transmit faster then 44100 * 2 channels * 2 bytes = 176400 bytes per
+ * second. Using a SPI communication this gives 176400 * 8 =
+ * 1'411'200 bps!
+ *
+ * Untested DRAFT implementation!
+ */
+#include <SPI.h>
+
+#include "AudioTools.h"
+
+const size_t BUFFER_SIZE = 1024;
+const int SPI_CLOCK = 2000000;  // 2 MHz
+AudioInfo info(44100, 2, 16);   //
+Vector<uint8_t> buffer(BUFFER_SIZE);
+SineWaveGenerator<int16_t> sineWave(32000);
+GeneratedSoundStream<int16_t> sound(sineWave);
+
+void setup() {
+  SPI.begin();
+  sineWave.begin(info, N_B4);
+  SPI.beginTransaction(SPISettings(SPI_CLOCK, MSBFIRST, SPI_MODE0));
+}
+
+void loop() {
+  // get data
+  size_t result = sound.readBytes(&buffer[0], buffer.size());
+  // transmit data
+  SPI.transfer(&buffer[0], result);
+  //SPI.endTransaction();
+}