step-sequencer/README.md

A step-sequencer for Node.js

# step-sequencer

An EventEmitter-based step-sequencer for Node.js.

# Usage
```javascript
var StepSequencer = require('step-sequencer');

// Instantiate a new StepSequencer object
var tempo = 120;
var division = 4;
var sequence = [0, 1, 2, 3];
var stepSequencer = new StepSequencer(tempo, division, sequence);

// The StepSequencer emits the number of
// the step when that step is to be played
stepSequencer.on('0', function (step) {
    console.log(step);
})
.on('1', function (step) {
    console.log(step);
})
.on('2', function (step) {
    console.log(step);
})
.on('3', function (step) {
    console.log(step);
});

// Begin playing the sequence
stepSequencer.play();
// 0
// 1
// 2
// 3 ...
```

# API

## StepSequencer.constructor

Constructrs the `StepSequencer` object:
```javascript
var stepSequencer = new StepSequencer(tempo = 120, division = 4, sequence = []);
```

- `tempo` is the tempo of playback
- `division` is the number of beats per measure
- `sequence` is the sequence of data to be emitted

## StepSequencer.prototype.play

Begins playing the sequence:
```javascript
stepSequencer.play();
// 0
// 1
// 2
// 3 ...
```

## StepSequencer.prototype.stop

Stops playing the sequence, does not reset the current step:
```javascript
// 0
// 1
stepSequencer.stop();
```

## StepSequencer.prototype.resume

Resumes playing from the current step. Continued from the previous example:
```javascript
stepSequencer.resume();
// 2
// 3 ...
```

## StepSequencer.prototype.setTempo

Sets the tempo, even if the `stepSequencer` is playing:
```javascript
stepSequencer.setTempo(120);
```

## StepSequencer.prototype.setSequence

Sets the division and sequence, even if the `stepSequencer` is playing.

The tempo is updated as well, if the division changes:
```javascript
stepSequencer.setSequence(4, [1, 2, 3, 4]);
```

# License

MIT