ELK-BLEDOM led controller using nodejs noble

elkbledom-noble.js

const noble = require('@abandonware/noble');

noble.on('stateChange', (state) => {
  if (state === 'poweredOn') {
    noble.startScanningAsync([], false);
  }
});

function buildColorBuffer(r, g, b) {
  return Buffer.from([0x7e, 0x00, 0x05, 0x03, r, g, b, 0x00, 0xef]);
}

noble.on('discover', async (peripheral) => {
  if (peripheral.advertisement.localName.includes("ELK-BLEDOM")) {
    noble.stopScanning();
    await peripheral.connectAsync();
    console.log('connected to peripheral: ' + peripheral.uuid);
    const { characteristics } = await peripheral.discoverAllServicesAndCharacteristicsAsync();
    const writer = characteristics.find((c) => c.properties.includes("writeWithoutResponse"));
    writer.writeAsync(buildColorBuffer(0, 0, 255), true);
  }
});