Add MIDIUSB.h compatibility for Teensy 2.0

teensy/MIDIUSB.h

@@ -0,0 +1,53 @@
+#ifndef MIDIUSB_h
+#define MIDIUSB_h
+
+// For compatibility with Arduino's MIDIUSB library
+
+#ifdef __cplusplus
+#if !defined(USB_MIDI)
+#error "Please select MIDI in Tools > USB Type to use MIDIUSB.h"
+#endif
+
+#include "usb_api.h"
+
+typedef struct {
+  struct {
+	uint8_t header;
+	uint8_t byte1;
+	uint8_t byte2;
+	uint8_t byte3;
+  };
+} midiEventPacket_t;
+
+
+class MIDI_
+{
+public:
+	constexpr MIDI_(void) { }
+	uint32_t available(void) {
+		return usbMIDI.midiusb_available();
+	}
+	midiEventPacket_t read(void) {
+		midiEventPacket_t event;
+		usbMIDI.midiusb_read((uint8_t *)&event);
+		return event;
+	}
+	void flush(void) {
+		usbMIDI.send_now();
+	}
+	void sendMIDI(midiEventPacket_t event) {
+		usbMIDI.send_raw(event.header, event.byte1, event.byte2, event.byte3);
+	}
+	size_t write(const uint8_t *buffer, size_t size) {
+		// TODO - is this really needed?
+		return 0;
+	}
+	operator bool() {
+		// TODO - is this really needed?
+		return true;
+	}
+};
+extern MIDI_ MidiUSB;
+
+#endif // __cplusplus
+#endif // MIDIUSB_h

usb_midi/usb_api.cpp

@@ -167,7 +167,67 @@ uint8_t usb_midi_class::analog2velocity(uint16_t val, uint8_t range)
 
 
 
+uint32_t usb_midi_class::midiusb_available()
+{
+	uint8_t c, intr_state;
+
+	intr_state = SREG;
+	cli();
+	if (!usb_configuration) {
+		SREG = intr_state;
+		return 0;
+	}
+	UENUM = MIDI_RX_ENDPOINT;
+	retry:
+	c = UEINTX;
+	if (!(c & (1<<RWAL))) {
+		if (c & (1<<RXOUTI)) {
+			UEINTX = 0x6B;
+			goto retry;
+		}
+		SREG = intr_state;
+		return 0;
+	}
+	SREG = intr_state;
+	return 4;
+}
 
+void usb_midi_class::midiusb_read(uint8_t *buf)
+{
+	uint8_t c, intr_state;
+
+	intr_state = SREG;
+	cli();
+	if (!usb_configuration) {
+		SREG = intr_state;
+		buf[0] = 0;
+		buf[1] = 0;
+		buf[2] = 0;
+		buf[3] = 0;
+		return;
+	}
+	UENUM = MIDI_RX_ENDPOINT;
+	retry:
+	c = UEINTX;
+	if (!(c & (1<<RWAL))) {
+		if (c & (1<<RXOUTI)) {
+			UEINTX = 0x6B;
+			goto retry;
+		}
+		SREG = intr_state;
+		buf[0] = 0;
+		buf[1] = 0;
+		buf[2] = 0;
+		buf[3] = 0;
+		return;
+	}
+	buf[0] = UEDATX;
+	buf[1] = UEDATX;
+	buf[2] = UEDATX;
+	buf[3] = UEDATX;
+	if (!(UEINTX & (1<<RWAL))) UEINTX = 0x6B;
+	SREG = intr_state;
+}
 
 
 bool usb_midi_class::read(uint8_t channel)

usb_midi/usb_api.h

@@ -258,6 +258,8 @@ public:
 	}
 private:
 	void send_raw(uint8_t b0, uint8_t b1, uint8_t b2, uint8_t b3);
+	uint32_t midiusb_available();
+	void midiusb_read(uint8_t *buf);
 	void sendSysEx_BufferHasTerm(uint16_t length, const uint8_t *data);
 	void sendSysEx_AddTermBytes(uint16_t length, const uint8_t *data);
 	void read_sysex_byte(uint8_t b);
@@ -287,6 +289,7 @@ private:
 	void (*handleActiveSensing)(void);
 	void (*handleSystemReset)(void);
 	void (*handleRealTimeSystem)(uint8_t rtb);
+	friend class MIDI_;
 };
 
 extern usb_midi_class usbMIDI;