| Namespace | Windows.Devices.Midi2.Utilities.SysExTransfer |
|---|---|
| Type Name | MidiSystemExclusiveSender |
| Type | WinRT Runtime Class |
| IDL | MidiSystemExclusiveSender.idl |
This static class sends MIDI 1.0 System Exclusive (SysEx 7) data to an open endpoint connection. It reads the source data from a stream, turns it into SysEx 7 UMP messages, sends those messages to the destination endpoint and group, and reports progress along the way.
Sending a large SysEx dump as fast as possible can overwhelm the receiving device. So the send method lets you slow the transfer down, by pausing for a while after every n messages.
The method returns an IAsyncOperationWithProgress that reports progress with MidiSystemExclusiveSendProgress, and finishes with true when the whole transfer works. You can cancel the operation.
| Static Method | Description |
|---|---|
SendBinarySysEx7ByteDataAsync(destinationConnection, destinationGroup, dataSource, preferredSingleTransferMessageCount, transferSpacingMilliseconds, converterState) |
Reads MIDI 1.0 bytestream SysEx data from dataSource, turns it into SysEx 7 UMP messages, and sends them to the destination endpoint and group |
| Parameter | Description |
|---|---|
destinationConnection |
The MidiEndpointConnection to send the data to. It must already be open |
destinationGroup |
The MidiGroup to send the messages to |
dataSource |
An IInputStream with the raw MIDI 1.0 bytestream SysEx data, including the 0xF0 start and 0xF7 end bytes. This is usually a stream opened on a .syx file |
preferredSingleTransferMessageCount |
How many messages to send before pausing for transferSpacingMilliseconds. Set this, or transferSpacingMilliseconds, to zero to send without pausing |
transferSpacingMilliseconds |
How long to pause after each batch of preferredSingleTransferMessageCount messages. Use it to give the receiving device time to handle the data |
converterState |
A MidiBytestreamToUmpMessageConverterState that holds the conversion state for this transfer |
The data in dataSource must be MIDI 1.0 bytestream System Exclusive data, not UMP data. Everything in the stream must convert into SysEx 7 (64-bit data) messages. If the data holds any other kind of message, the operation fails.
All the arguments are required. The operation fails if any of them is null, or if destinationConnection isn’t open.
var file = await StorageFile.GetFileFromPathAsync(sysExFilePath);
using (var stream = await file.OpenReadAsync())
{
var converterState = new MidiBytestreamToUmpMessageConverterState();
var operation = MidiSystemExclusiveSender.SendBinarySysEx7ByteDataAsync(
connection,
new MidiGroup(0),
stream,
100, // send 100 messages at a time
20, // then wait 20ms before continuing
converterState);
operation.Progress = (op, progress) =>
{
Console.WriteLine($"Read {progress.CountBytesRead} bytes, sent {progress.CountMessagesSent} messages");
};
bool success = await operation;
}
These samples send a .syx file to a device. They replace the WinMM steps of midiOutPrepareHeader, midiOutLongMsg, and midiOutUnprepareHeader, and the rules about how long each buffer has to stay around.
Windows MIDI Services is an open source project with all source available on GitHub. We have a great community on Discord as well. Between GitHub and Discord, you should find the information you are looking for.
