metawear

MetaWear JavaScript SDK

JavaScript SDK for creating MetaWear apps that run on node.js or in the browser (web-bluetooth support not widespread yet, but growing). This is a thin wrapper around the MetaWear C++ API so you will find the C++ documentation and API reference useful. Also, check out the JavaScript examples.

Under the hood it uses Noble for Bluetooth Low Energy communications.

Install

Before getting started, you need to setup the prerequisites for Noble. While you are there, familiarize yourself with the reset of the README since there a few limitiations and other gotchas spelled out.

Then you can simply install the NPM module:

npm install metawear

Usage

Require the metawear package

var MetaWear = require('metawear');

Discover the first MetaWear device seen

MetaWear.discover(function (device) { ... }

Or a specific MAC address

MetaWear.discoverByAddress('cb:7d:c5:b0:20:8f', function(device) { ... }

There are other options too, documented in Noble Device

After that, you must connect to the device

device.connectAndSetUp(function (error) { ... }

At this point you can call any of the MetaWear API's, for example, you can blink the LED green

var pattern = new MetaWear.LedPattern();
MetaWear.mbl_mw_led_load_preset_pattern(pattern.ref(), MetaWear.LedPreset.BLINK);
MetaWear.mbl_mw_led_write_pattern(device.board, pattern.ref(), MetaWear.LedColor.GREEN);
MetaWear.mbl_mw_led_play(device.board);

Complete Example

var MetaWear = require('metawear');

MetaWear.discover(function (device) {
  device.connectAndSetUp(function (error) {
    var pattern = new MetaWear.LedPattern();
    MetaWear.mbl_mw_led_load_preset_pattern(pattern.ref(), MetaWear.LedPreset.BLINK);
    MetaWear.mbl_mw_led_write_pattern(device.board, pattern.ref(), MetaWear.LedColor.GREEN);
    MetaWear.mbl_mw_led_play(device.board);
    // After 5 seconds we reset the board to clear the LED, when we receive
    // a disconnect notice we know the reset is complete, so exit the program
    setTimeout(function () {
      device.on('disconnect', function () {
        process.exit(0);
      });
      MetaWear.mbl_mw_debug_reset(device.board);
    }, 5000);
  });
});