// Start the port and setup buffers to receives Sysex
public string Start()
{
// Allocate buffer array
if (buffers == null)
{
const int numBuffers = 4;
const int bufferSize = 4096; // ZZZ Param?
buffers = new MidiBuffer[numBuffers];
// Allocate and prepare the buffers
for (int b = 0; b < buffers.Length; b++)
{
// Create buffer
buffers[b] = new MidiBuffer(bufferSize, (IntPtr)b);
// Prepare the buffer and give it to windows
EMMError st = buffers[b].AddMidiInBuffer(handle);
if (st != EMMError.NOERROR)
{
return(WindowsUtil.StrError(st));
}
}
}
// Finally, start the port
return(WindowsUtil.StrError(NativeMethods.midiInStart(handle)));
}
// Close the port
public string Close()
{
EMMError result = NativeMethods.midiOutClose(handle);
handle = IntPtr.Zero;
return(WindowsUtil.StrError(result));
}
// Close the port
public string Close()
{
Stop();
Reset();
EMMError result = NativeMethods.midiInClose(handle);
handle = IntPtr.Zero;
MidiInputReceived = null;
return(WindowsUtil.StrError(result));
}
// Open the input port.
public string Open()
{
// Open the port
var st = NativeMethods.midiOutOpen(
out handle,
Id,
null,
IntPtr.Zero,
0);
return(WindowsUtil.StrError(st));
}
// Reset the port and free the sysex buffers
public string Reset()
{
EMMError st = NativeMethods.midiInReset(handle);
if (st == EMMError.NOERROR && buffers != null)
{
// The buffers have now been released by the callback. Just free the array.
buffers = null;
}
return(WindowsUtil.StrError(st));
}
// Open the input port. Midi events cause the MidiInputReceived event to be raised
public string Open()
{
// Open the port
EMMError st = NativeMethods.midiInOpen(
out handle,
id,
midiInProc,
IntPtr.Zero,
NativeMethods.CALLBACK_FUNCTION);
return(WindowsUtil.StrError(st));
}
// Send a message
public string Send(MidiMessage m)
{
var st = EMMError.NOERROR;
if (m is MidiSysexMessage)
{
// Sysex messages are sent using a buffer.
var sysex = m as MidiSysexMessage;
var buffer = new MidiBuffer(sysex.Body);
using (buffer)
{
// Prepare the buffer
st = buffer.PrepareForMidiOut(handle);
if (st == EMMError.NOERROR)
{
// Send the sysex
st = NativeMethods.midiOutLongMsg(handle, buffer.Header, buffer.HeaderSize);
}
if (st == EMMError.NOERROR)
{
// Wait until it is sent
// Note: this is simple but weak... If performance becomes necessary
// we can declare a callback, not wait here (just queue the buffer) and
// unprepare it when we receive the appropriate message in the callback
while (!buffer.IsFree())
{
Thread.Sleep(1);
}
// unprepare the buffer
st = buffer.UnprepareForMidiOut(handle);
}
}
}
else
{
uint sm = m.GetAsShortMessage();
if (sm != uint.MaxValue)
{
st = NativeMethods.midiOutShortMsg(handle, sm);
}
}
return(WindowsUtil.StrError(st));
}
// Reset the port
public string Reset()
{
return(WindowsUtil.StrError(NativeMethods.midiOutReset(handle)));
}
// Stop the port
public string Stop()
{
return(WindowsUtil.StrError(NativeMethods.midiInStop(handle)));
}
