Secure context

This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The open() method of the MIDIPort interface makes the MIDI device connected to this MIDIPort explicitly available.

If the port is successfully opened a new MIDICOnnectionEvent is queued to the MIDIPort.onstatechange and MIDIAccess.onstatechange event handlers, and the MIDIPort.connection property is changed to "open".

If the port is already open when this method is called, then the promise will resolve successfully.


var output = midiAccess.outputs.get(portID);
output.open(); // opens the port



Return value

A Promise which resolves once access to the port has been successfully obtained.


DOMException InvalidAccessError
The promise is rejected with this error if the port is unavailable and cannot be opened.


The following example shows an output port being opened.

var output = midiAccess.outputs.get(portID);
output.open(); // opens the port


No specification found

No specification data found for api.MIDIPort.open.
Check for problems with this page or contribute a missing spec_url to mdn/browser-compat-data. Also make sure the specification is included in w3c/browser-specs.

Browser compatibility

BCD tables only load in the browser