Add attachInterrupt to MIDIUSB.h

examples/MIDIUSB_read_with_interrupts/MIDIUSB_read_with_interrupts.ino

@@ -0,0 +1,65 @@
+/*
+ * MIDIUSB_test.ino
+ *
+ * Modifed to use interrupts. 12/12/2020 
+ * Doug Clauder https://github.com/studiohsoftware
+ *
+ * Created: 4/6/2015 10:47:08 AM
+ * Author: gurbrinder grewal
+ * Modified by Arduino LLC (2015)
+ */ 
+
+#include "MIDIUSB.h"
+
+// First parameter is the event type (0x09 = note on, 0x08 = note off).
+// Second parameter is note-on/note-off, combined with the channel.
+// Channel can be anything between 0-15. Typically reported to the user as 1-16.
+// Third parameter is the note number (48 = middle C).
+// Fourth parameter is the velocity (64 = normal, 127 = fastest).
+
+void noteOn(byte channel, byte pitch, byte velocity) {
+  midiEventPacket_t noteOn = {0x09, 0x90 | channel, pitch, velocity};
+  MidiUSB.sendMIDI(noteOn);
+}
+
+void noteOff(byte channel, byte pitch, byte velocity) {
+  midiEventPacket_t noteOff = {0x08, 0x80 | channel, pitch, velocity};
+  MidiUSB.sendMIDI(noteOff);
+}
+
+void setup() {
+  Serial1.begin(115200);
+  MidiUSB.attachInterrupt(onEvent);
+}
+
+// First parameter is the event type (0x0B = control change).
+// Second parameter is the event type, combined with the channel.
+// Third parameter is the control number number (0-119).
+// Fourth parameter is the control value (0-127).
+
+void controlChange(byte channel, byte control, byte value) {
+  midiEventPacket_t event = {0x0B, 0xB0 | channel, control, value};
+  MidiUSB.sendMIDI(event);
+}
+
+void loop() {
+
+}
+
+void onEvent(int ep) {
+    USB->DEVICE.INTENCLR.reg = 0xFF; //SAMD interrupts continuously without this.
+    midiEventPacket_t rx;
+    do {
+      rx = MidiUSB.read();
+      if (rx.header != 0) {
+        Serial1.print("Received: ");
+        Serial1.print(rx.header, HEX);
+        Serial1.print("-");
+        Serial1.print(rx.byte1, HEX);
+        Serial1.print("-");
+        Serial1.print(rx.byte2, HEX);
+        Serial1.print("-");
+        Serial1.println(rx.byte3, HEX);
+      }
+    } while (rx.header != 0);
+}

src/MIDIUSB.h

@@ -224,6 +224,8 @@ class MIDI_ : public PluggableUSBModule
   bool setup(USBSetup& setup);
   /// MIDI Device short name, defaults to "MIDI" and returns a length of 4 chars
   uint8_t getShortName(char* name);
+  void (*interruptCallback)(int /* ep */);
+  virtual void handleEndpoint(int ep) { if (interruptCallback) interruptCallback(ep); }
 
 public:
 	/// Creates a MIDI USB device with 2 endpoints
@@ -240,6 +242,8 @@ class MIDI_ : public PluggableUSBModule
 	size_t write(const uint8_t *buffer, size_t size);
 	/// NIY
 	operator bool();
+	void attachInterrupt(void(*function)(int /* ep */)){interruptCallback = function;};
+
 };
 extern MIDI_ MidiUSB;