Read data from Dymo M10 scale using nodejs in Windows.

app.js

var HID = require('node-hid'),
    usb = require('usb');

var reading = false,
    interval,
    vid = 0x922,
    pid = 0x8003;

// try to connect to the scale if available
startReading();

usb.on('attach', function (device) {
    if (device.deviceDescriptor.idVendor === vid && device.deviceDescriptor.idProduct === pid) {
        console.log('Dymo M10 attached');

        interval = setInterval(startReading, 1000);
    }
});

usb.on('detach', function (device) {
    if (device.deviceDescriptor.idVendor === vid && device.deviceDescriptor.idProduct === pid) {
        console.log('Dymo M10 detached');
        reading = false;
        clearInterval(interval);
    }
});

function startReading() {
    if (reading) return;
    try {
        var d = new HID.HID(vid, pid);

        console.log('Starting to read data from scale');
        reading = true;

        d.on("data", function (data) {
            var buf = new Buffer(data);
            var grams = buf[4] + (256 * buf[5]);
            console.log(new Date().toISOString() + ': ' + grams + ' grams');
        });

        d.on("error", function (error) {
            console.log(error);
            reading = false;
            d.close();
        });
    } catch (err) {
        if (/cannot open device/.test(err.message)) {
            console.log('Dymo M10 cannot be found');
        } else
            console.log(err);
    }
}