Node.js program to update LEDs via a serial-over-USB connected Arduino for my Christmas Jumper project

xmas.js

var SerialPort = require("serialport");
var tinycolor2 = require("tinycolor2");
var request = require('request');

var portdev = "/dev/ttyACM0";
var port = new SerialPort(portdev, {
  baudRate: 9600,
});

port.on('error', function(err) {
  console.log('Error: ', err.message);
})

port.on('data', function (data) {
  console.log('Data: ' + data);
});

setInterval(function() {
  request('http://api.thingspeak.com/channels/1417/field/2/last.json', { json: true }, (err, res, body) => {
    if (err) { return console.log(err); }

    var c = tinycolor2(body.field2).toRgb();
    // Divide all values by 4 to reduce brightness and power usage
    var r = c.r / 4;
    var g = c.g / 4;
    var b = c.b / 4;

    // These LEDs have red and green swapped
    var x = "COLOR " + tinycolor2({ r: g, g: r, b: b }).toHexString() + "\n";
    port.write(x);
  });
}, 5000);