Diff: MIDIMessage.h

Revision:

0:56b095524cf2

Child:

1:ff74eabe02cd

diff -r 000000000000 -r 56b095524cf2 MIDIMessage.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MIDIMessage.h	Sun Feb 06 17:26:29 2011 +0000
@@ -0,0 +1,161 @@
+/* MIDI Message Format
+ * 
+ * [ msg(4) | channel(4) ] [ 0 | n(7) ] [ 0 | m(7) ]
+ *
+ * MIDI Data Messages (Channel Specific)
+ *
+ * Message               msg n    m
+ * ---------------------------------------------
+ * Note Off	             0x8 Key        Velocity
+ * Note On	             0x9 Key        Velocity
+ * Polyphonic Aftertouch 0xA Key        Pressure
+ * Control Change        0xB Controller Value
+ * Program Change        0xC Program    -
+ * Channel Aftertouch    0xD Pressure   -
+ * Pitch Wheel           0xE LSB        MSB
+ */
+
+
+#ifndef MBED_MIDIMESSAGE_H
+#define MBED_MIDIMESSAGE_H
+
+class MIDIMessage {
+public:
+	
+	// create messages
+	
+	static MIDIMessage NoteOff(int key, int velocity = 127, int channel = 0) {
+		MIDIMessage msg;
+		msg.data[0] = 0x80 | (channel & 0x0F);
+		msg.data[1] = key & 0x7F;
+		msg.data[2] = velocity & 0x7F; 
+		return msg;
+	}
+	
+	static MIDIMessage NoteOn(int key, int velocity = 127, int channel = 0) {
+		MIDIMessage msg;
+		msg.data[0] = 0x90 | (channel & 0x0F);
+		msg.data[1] = key & 0x7F;
+		msg.data[2] = velocity & 0x7F; 				
+		return msg;
+	}
+	
+	static MIDIMessage PolyphonicAftertouch(int key, int pressure, int channel = 0) {
+		MIDIMessage msg;
+		msg.data[0] = 0xA0 | (channel & 0x0F);
+		msg.data[1] = key & 0x7F;
+		msg.data[2] = pressure & 0x7F; 		
+		return msg;
+	}
+	
+	static MIDIMessage ControlChange(int control, int value, int channel = 0) {
+		MIDIMessage msg;
+		msg.data[0] = 0xB0 | (channel & 0x0F);
+		msg.data[1] = control & 0x7F;
+		msg.data[2] = value & 0x7F; 		
+		return msg;
+	}
+	
+	static MIDIMessage ProgramChange(int program, int channel = 0) {
+		MIDIMessage msg;
+		msg.data[0] = 0xC0 | (channel & 0x0F);
+		msg.data[1] = program & 0x7F;
+		msg.data[2] = 0x00; 		
+		return msg;
+	}
+	
+	static MIDIMessage ChannelAftertouch(int pressure, int channel = 0) {
+		MIDIMessage msg;
+		msg.data[0] = 0xD0 | (channel & 0x0F);
+		msg.data[1] = pressure & 0x7F;
+		msg.data[2] = 0x00; 		
+		return msg;
+	}
+	
+	static MIDIMessage PitchWheel(int pitch = 0, int channel = 0) {
+		MIDIMessage msg;
+		int p = pitch + 8192;	// 0 - 16383, 8192 is center
+		msg.data[0] = 0xE0 | (channel & 0x0F);
+		msg.data[1] = p & 0x7F;
+		msg.data[2] = (p >> 7) & 0x7F; 				
+		return msg;
+	}
+	
+	static MIDIMessage AllNotesOff(int channel = 0) {
+		return ControlChange(123, 0, channel);
+	}
+	
+	// decode messages
+	enum MIDIMessageType {
+		ErrorType,
+		NoteOffType,
+		NoteOnType,
+		PolyphonicAftertouchType,
+		ControlChangeType,
+		ProgramChangeType,
+		ChannelAftertouchType,
+		PitchWheelType,
+		AllNotesOffType
+	};
+	
+	MIDIMessageType type() {
+		switch((data[0] >> 4) & 0xF) {
+			case 0x8: return NoteOffType;
+			case 0x9: return NoteOnType;
+			case 0xA: return PolyphonicAftertouchType;
+			case 0xB: 
+				if(controller() < 120) { // standard controllers
+					return ControlChangeType;
+				} else if(controller() == 123) {
+					return AllNotesOffType;
+				} else {
+					return ErrorType; // unsupported atm
+				}
+			case 0xC: return ProgramChangeType;
+			case 0xD: return ChannelAftertouchType;
+			case 0xE: return PitchWheelType;
+			default: return ErrorType;
+		}
+	}
+	
+	int channel() {
+		return (data[0] & 0x0F);
+	}
+	
+	int key() {
+		return (data[1] & 0x7F);		
+	}
+	
+	int velocity() {
+		return (data[2] & 0x7F);		
+	}
+
+	int value() {
+		return (data[2] & 0x7F);		
+	}
+	
+	int pressure() {
+		if(type() == PolyphonicAftertouchType) {
+			return (data[2] & 0x7F);		
+		} else {
+			return (data[1] & 0x7F);		
+		}
+	}
+
+	int controller() {
+		return (data[1] & 0x7F);		
+	}
+
+	int program() {
+		return (data[1] & 0x7F);		
+	}
+	
+	int pitch() {
+		int p = ((data[2] & 0x7F) << 7) | (data[1] & 0x7F);
+		return p - 8192; // 0 - 16383, 8192 is center
+	}
+	
+	uint8_t data[3];
+};	
+
+#endif