arduino_midi_library/src/midi_UsbTransport.hpp

181 lines
5.1 KiB
C++

/*!
* @file midi_UsbTransport.hpp
* Project Arduino MIDI Library
* @brief MIDI Library for the Arduino - Transport layer for USB MIDI
* @author Francois Best
* @date 10/10/2016
* @license MIT - Copyright (c) 2016 Francois Best
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#pragma once
BEGIN_MIDI_NAMESPACE
template<unsigned BufferSize>
inline UsbTransport<BufferSize>::UsbTransport()
{
}
template<unsigned BufferSize>
inline UsbTransport<BufferSize>::~UsbTransport()
{
}
// -----------------------------------------------------------------------------
template<unsigned BufferSize>
inline void UsbTransport<BufferSize>::begin(unsigned inBaudrate)
{
mTxBuffer.clear();
mRxBuffer.clear();
}
template<unsigned BufferSize>
inline unsigned UsbTransport<BufferSize>::available()
{
pollUsbMidi();
return mRxBuffer.getLength();
}
template<unsigned BufferSize>
inline byte UsbTransport<BufferSize>::read()
{
return mRxBuffer.read();
}
template<unsigned BufferSize>
inline void UsbTransport<BufferSize>::write(byte inData)
{
mTxBuffer.write(inData);
recomposeAndSendTxPackets();
}
// -----------------------------------------------------------------------------
template<unsigned BufferSize>
inline bool UsbTransport<BufferSize>::pollUsbMidi()
{
bool received = false;
midiEventPacket_t packet = MidiUSB.read();
while (packet.header != 0)
{
received = true;
switch (packet.header << 4)
{
// 3 bytes messages
case midi::NoteOff:
case midi::NoteOn:
case midi::AfterTouchPoly:
case midi::ControlChange:
case midi::PitchBend:
mRxBuffer.write(packet.byte1);
mRxBuffer.write(packet.byte2);
mRxBuffer.write(packet.byte3);
break;
// 2 bytes messages
case midi::ProgramChange:
case midi::AfterTouchChannel:
mRxBuffer.write(packet.byte1);
mRxBuffer.write(packet.byte2);
break;
// 1 byte message
case midi::TuneRequest:
case midi::Clock:
case midi::Start:
case midi::Continue:
case midi::Stop:
case midi::ActiveSensing:
case midi::SystemReset:
mRxBuffer.write(packet.byte1);
break;
// Special cases
// case midi::SystemExclusive:
// case midi::TimeCodeQuarterFrame:
// case midi::SongPosition:
// case midi::SongSelect:
// break;
default:
break;
}
packet = MidiUSB.read();
}
return received;
}
template<unsigned BufferSize>
inline void UsbTransport<BufferSize>::recomposeAndSendTxPackets()
{
while (!mTxBuffer.isEmpty())
{
const byte data = mTxBuffer.read();
if (mCurrentTxPacketByteIndex == 0)
{
mCurrentTxPacket.mPacket.header = encodePacketHeader(data);
}
else
{
mCurrentTxPacket.mDataArray[mCurrentTxPacketByteIndex] = data;
}
mCurrentTxPacketByteIndex++;
const int packetLength = getPacketLength(mCurrentTxPacket.mPacket);
if (mCurrentTxPacketByteIndex == packetLength)
{
MidiUSB.write(mCurrentTxPacket.mDataArray, packetLength);
resetTx();
}
}
}
template<unsigned BufferSize>
inline void UsbTransport<BufferSize>::resetTx()
{
mCurrentTxPacket.mPacket.header = 0;
mCurrentTxPacket.mPacket.byte1 = 0;
mCurrentTxPacket.mPacket.byte2 = 0;
mCurrentTxPacket.mPacket.byte3 = 0;
mCurrentTxPacketByteIndex = 0;
}
template<unsigned BufferSize>
inline byte UsbTransport<BufferSize>::encodePacketHeader(StatusByte inStatusByte)
{
// todo: fix me for other types than channel
return inStatusByte >> 4;
}
template<unsigned BufferSize>
inline int UsbTransport<BufferSize>::getPacketLength(const midiEventPacket_t& inPacket)
{
return 3;
}
END_MIDI_NAMESPACE