MIDIOutput: send() method

The send() method of the MIDIOutput interface queues messages for the corresponding MIDI port. The message can be sent immediately, or with an optional timestamp to delay sending.

Syntax

send(data)
send(data, timestamp)

Parameters

data

A sequence of one or more valid MIDI messages. Each entry represents a single byte of data.

timestamp Optional

A DOMHighResTimestamp with the time in milliseconds when the message should be sent (relative to Performance.timeOrigin).

Return value

None (undefined).

Exceptions

TypeError

Thrown if data is not a valid sequence, or does not contain a valid MIDI message.

InvalidAccessError DOMException

Thrown if data is a system exclusive message, and the MIDIAccess did not enable exclusive access.

InvalidStateError DOMException

Thrown if the port is disconnected.

Examples

In the following example a middle C note is sent immediately, followed by a note off message one second later.

function sendMiddleC(midiAccess, portID) {
  const noteOnMessage = [0x90, 60, 0x7f]; // Note on middle C, full velocity
  const output = midiAccess.outputs.get(portID);
  output.send(noteOnMessage); // Omitting the timestamp means send immediately.
  output.send([0x80, 60, 0x40], window.performance.now() + 1000.0); // timestamp = now + 1000ms.
}

Specifications

Browser compatibility