1 files changed, 110 insertions, 0 deletions
diff --git a/circuitpython/lib/mp3/src/Adafruit_MP3.h b/circuitpython/lib/mp3/src/Adafruit_MP3.h
new file mode 100644
index 0000000..6f524ad
--- /dev/null
+++ b/circuitpython/lib/mp3/src/Adafruit_MP3.h
@@ -0,0 +1,110 @@
+#ifndef LIB_ADAFRUIT_MP3_H
+#define LIB_ADAFRUIT_MP3_H
+
+#include "Arduino.h"
+
+#if defined(__MK66FX1M0__) || defined(__MK64FX512__) || defined(__MK20DX256__)|| defined(NRF52)	// teensy 3.6, 3.5, 3.1/2, or Adafruit Feather nRF52
+#define ARM_MATH_CM4
+#endif
+
+#include "arm_math.h"
+#include "mp3dec.h"
+
+//TODO: decide on a reasonable buffer size
+#if defined(NRF52)
+#define MP3_OUTBUF_SIZE (4 * 1024)
+#define MP3_INBUF_SIZE (2 * 1024)
+
+#define BUFFER_LOWER_THRESH (1 * 1024)
+#else
+#define MP3_OUTBUF_SIZE (4 * 1024)
+#define MP3_INBUF_SIZE (2 * 1024)
+
+#define BUFFER_LOWER_THRESH (1 * 1024)
+#endif
+
+#define MP3_SAMPLE_RATE_DEFAULT 44100
+
+#if defined(__SAMD51__) // feather/metro m4
+
+#define MP3_TC TC2
+#define MP3_IRQn TC2_IRQn
+#define MP3_Handler TC2_Handler
+#define MP3_GCLK_ID TC2_GCLK_ID
+#define MP3_DMA_TRIGGER TC2_DMAC_ID_MC_0
+
+#elif defined(NRF52)
+
+#define MP3_TIMER NRF_TIMER1
+#define MP3_IRQn TIMER1_IRQn
+#define MP3_Handler TIMER1_IRQHandler
+
+#endif
+
+struct Adafruit_MP3_outbuf {
+	volatile int count;
+	int16_t buffer[MP3_OUTBUF_SIZE];
+};
+
+class Adafruit_MP3 {
+public:
+	Adafruit_MP3() : hMP3Decoder() { inbufend = (inBuf + MP3_INBUF_SIZE); }
+	~Adafruit_MP3() { MP3FreeDecoder(hMP3Decoder); };
+	bool begin();
+	void setBufferCallback(int (*fun_ptr)(uint8_t *, int));
+	void setSampleReadyCallback(void (*fun_ptr)(int16_t, int16_t));
+		
+	void play();
+	void pause();
+	void resume();
+	
+	int tick();
+
+#if defined(__MK66FX1M0__) || defined(__MK64FX512__) || defined(__MK20DX256__) // teensy 3.6, 3.5, or 3.1/2
+	static IntervalTimer _MP3Timer;
+	static uint32_t currentPeriod;
+#endif
+
+	static uint8_t numChannels;
+	
+protected:
+#if defined(__SAMD51__) // feather/metro m4
+	Tc *_tc;
+#endif
+	HMP3Decoder hMP3Decoder;
+	
+	volatile int bytesLeft;
+	uint8_t *readPtr;
+	uint8_t *writePtr;
+	uint8_t inBuf[MP3_INBUF_SIZE];
+	uint8_t *inbufend;
+	bool playing = false;
+	
+	int (*bufferCallback)(uint8_t *, int);
+	int findID3Offset(uint8_t *readPtr);
+
+};
+
+class Adafruit_MP3_DMA : public Adafruit_MP3 {
+public:
+	Adafruit_MP3_DMA() : Adafruit_MP3() {
+		framebuf = NULL;
+		decodeCallback = NULL;
+	}
+	~Adafruit_MP3_DMA() {
+		if(framebuf != NULL) free(framebuf);
+	}
+
+	void getBuffers(int16_t **ping, int16_t **pong);
+	void setDecodeCallback(void (*fun_ptr)(int16_t *, int)) { decodeCallback = fun_ptr; }
+
+	void play();
+	int fill();
+private:
+	int16_t *framebuf, *leftover;
+	int leftoverSamples;
+	MP3FrameInfo frameInfo;
+	void (*decodeCallback)(int16_t *, int);
+};
+
+#endif