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@janjongboom
Created May 18, 2015 12:42
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iBeacon scanning Firefox OS
navigator.mozBluetooth.defaultAdapter.startLeScan([]).then(handle => {
console.log('Start scanning', handle);
handle.ondevicefound = e=> {
var record = parseScanRecord(e.scanRecord);
if (record) {
console.log('Found an iBeacon', record.uuid, record.major, record.minor, e.rssi);
}
}
setTimeout(() => {
console.log('Stop scanning');
navigator.mozBluetooth.defaultAdapter.stopLeScan(handle)
}, 5000);
}, err => console.error(err))
function parseScanRecord(scanRecord) {
var view = new Uint8Array(scanRecord);
// Company ID does not have fixed length, so find out where to start by
// finding 0x02, 0x15 in byes 4..8
for (var start = 4; start < 8; start++) {
if (view[start] === 0x02 && view[start + 1] === 0x15) {
break;
}
}
if (start === 8) {
return;
}
// Now UUID is the next 16 bytes right after 0x15
start += 2;
var uuid = bytesToHex(view.slice(start, start + 16));
// major / minor are two bytes each
start += 16;
var major = (view[start] & 0xff) * 0x100 + (view[start + 1] & 0xff);
start += 2;
var minor = (view[start] & 0xff) * 0x100 + (view[start + 1] & 0xff);
return { uuid: uuid, major: major, minor: minor };
}
var hexArray = '0123456789ABCDEF'.split('');
function bytesToHex(bytes) {
var hex = [];
for (var j = 0; j < bytes.length; j++) {
var v = bytes[j] & 0xff;
hex[j * 2] = hexArray[v >>> 4];
hex[j * 2 + 1] = hexArray[v & 0x0f];
}
return hex.join('');
}
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