What to do when Arduino sends empty ArrayBuffer to NW.js?

I've been playing around with the MPR121-Shield Capacitive Touch Sensor by Adafruit. In Arduino's IDE, there is an example of code you can simply download and run, and it works perfectly : when I touch on the pin 11, for example, it returns ''11 touched'', and when I release it, it returns ''11 pressed''. Great!

Now the problem comes when I try to transfer that data to NW.js. By using Chrome's serial port in NW.js, I can connect to the port in which my Arduino is connected, and try to read whichever data the Arduino is sending. However, as I try to read the data, the only thing I receive is an ArrayBuffer filled with bytes of 0. I am really not sure what is happening here, as both devices work perfectly when I run it in Arduino's IDE, but it returns basically nothing with chrome.serialport.

Does anyone have a tip or an idea of what's going on here? If I do a console.log(info.data), I only get an ArrayBuffer with empty bites.

Thanks

Here is my code :

const ab2str = require('arraybuffer-to-string');

nw.Window.get().showDevTools();

let buffer = "";

chrome.serial.getDevices(devices => {
  devices.forEach(device => console.log(device));
});

// let port = "COM3";
let port = "/dev/cu.usbmodem142401";

chrome.serial.connect(port, {bitrate: 1000000}, () => {
  console.log("Serialport connected:" + port);
  chrome.serial.onReceive.addListener(onDataReceived);
});

function onDataReceived(info) {

  let lines = ab2str(info.data).split("\n");
  lines[0] = buffer + lines[0];
  buffer = lines.pop();

  lines.forEach(line => {
    const [type, value] = line.split("=");
    console.log(type, value);
  });

}

Solution

The Tx and Rx baud rates has to be the same to properly decode the information, and the arduino IDE handles that for you in the first case, but you will need to handle it manually for the second case. In serial port communication, single bit is transferred at a time unlike in parallel ports where you will have all bits availed at the same time for reading. So, in serial ports, the rate at which the information is transmitted(Tx) should be the same as the rate at which the information is received(Rx), otherwise bits could be lost and you may get a wrong information. The arduino IDE handles most of these issues for you, if I'm not wrong the IDE allows you to change the baud rate, but the default is 9600.