struct MIDIMsg {
	uint8_t	status;
	uint8_t	note;
	uint8_t	velocity;
};


// getMIDIMsg - Non-blocking receive of MIDI message:
// returns 0 if no MIDI message is ready
// 1 if a MIDI note on/off message is read
// Pays no attention to value of channel
uint8_t getMIDIMsg(struct MIDIMsg *msg) {
	uint8_t nul;
	
	// Don't block if message isn't ready
	if( !(UCSRA & (1 << RXC)) )
		return 0;
	
	// Otherwise load in status byte
	msg->status = UDR;

	// If note on or note off, then...
	if(((msg->status & 0xF0) == 0x90) || ((msg->status & 0xF0) == 0x80)) {
		// Wait for USART receive
		while( !(UCSRA & (1 << RXC)) );
		msg->note = UDR;
		// Wait for USART receive
		while( !(UCSRA & (1 << RXC)) );
		msg->velocity = UDR;
	} else {
		while( !(UCSRA & (1 << RXC)) );
		// Read next byte to clear register
		nul = UDR;
	}
		
	return 1;
}