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MIDIOutput
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The MIDIOutput interface of the Web MIDI API provides methods to add messages to the queue of an output device, and to clear the queue of messages.
This interface doesn't implement any specific properties, but inherits properties from MIDIPort.
The following example sends a middle C immediately on MIDI channel 1.
js
function sendMiddleC(midiAccess, portID) {
const noteOnMessage = [0x90, 60, 0x7f]; // note on, middle C, full velocity
const output = midiAccess.outputs.get(portID);
output.send(noteOnMessage); // sends the message.
}