@guillaumearm/easymidi
v2.0.3
Published
Simple event-based MIDI messaging
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node-easymidi
node-easymidi is a simple event-based MIDI messaging wrapper for node-midi.
Installation
Install with NPM:
npm install easymidi
Usage Overview
The module can interface with existing MIDI inputs/outputs or create virtual inputs/outputs. Here's a simple example to listen for note on events from an existing MIDI input:
var easymidi = require('easymidi');
var input = new easymidi.Input('MIDI Input Name');
input.on('noteon', function (msg) {
// do something with msg
});
Here's an example of sending a note on message to an existing MIDI output:
var easymidi = require('easymidi');
var output = new easymidi.Output('MIDI Output Name');
output.send('noteon', {
note: 64,
velocity: 127,
channel: 3
});
The Input and Output objects are EventEmitters and you can use the EventEmitter functions such as once()
, removeListener()
, and removeAllListeners()
as well.
Virtual Devices
Virtual devices can be created by passing a true
argument to the Input or Output constructors:
var virtualInput = new easymidi.Input('Virtual input name', true);
var virtualOutput = new easymidi.Output('Virtual output name', true);
Device Lists
You can get an array of existing MIDI input or output names using the getInputs()
and getOutputs
functions:
var inputs = easymidi.getInputs();
var outputs = easymidi.getOutputs();
Closing Devices
When you're finished with a MIDI device you can close()
it:
var input = new easymidi.Input('My input', true);
input.close();
var output = new easymidi.Output('My output', true);
output.close();
Message Reference
The following table describes the MIDI message types that are supported and the parameters of each:
| Type | Parameter | Parameter | Parameter | |--------------------|--------------------|------------------|----------------| | noteon | note [0-127] | velocity [0-127] | channel [0-15] | | noteoff | note [0-127] | velocity [0-127] | channel [0-15] | | poly aftertouch | note [0-127] | velocity [0-127] | channel [0-15] | | cc | controller [0-127] | value [0-127] | channel [0-15] | | program | number [0-127] | | channel [0-15] | | channel aftertouch | pressure [0-127] | | channel [0-15] | | pitch | value [0-16384] | | channel [0-15] | | position | value [0-16384] | | | | mtc | type [0-7] | value [0-15] | | | select | song [0-127] | | | | clock | | | | | start | | | | | continue | | | | | stop | | | | | activesense | | | | | reset | | | | | sysex | bytes (variable length array) | | |
Examples
Receive a noteon message:
input.on('noteon', function (params) {
// params = {note: ..., velocity: ..., channel: ...}
});
Send a control change message:
output.send('cc', {
controller: 37,
value: 80,
channel: 0
})
Listen for midi clock messages:
input.on('clock', function () {
// do something on every clock tick
});
Send a sysex message.
Throws an error if array does not start with 0xf0 (240) and end with 0xf7 (247).
output.send('sysex',[240, 126, 1, 6, 1, 247]);
See the example programs for more examples.