espruino-ble-uart
Version:
This is an Espruino Web Tool that implements the Nordic UART Service (NUS) by Nordic Semiconductors for BLE use. This allows BLE devices to communicate using UART via Bluetooth Low Energy.
508 lines (490 loc) • 20.3 kB
JavaScript
/* Copyright 2020 Gordon Williams, gw@pur3.co.uk
https://github.com/espruino/EspruinoWebTools
*/
(function (root, factory) {
if (typeof define === 'function' && define.amd) {
// AMD. Register as an anonymous module.
define([], factory);
} else if (typeof module === 'object' && module.exports) {
// Node. Does not work with strict CommonJS, but
// only CommonJS-like environments that support module.exports,
// like Node.
module.exports = factory();
} else {
// Browser globals (root is window)
root.UART = factory();
}
}(typeof self !== 'undefined' ? self : this, function () {
if (typeof navigator == "undefined") return;
var isBusy;
var queue = [];
function ab2str(buf) {
return String.fromCharCode.apply(null, new Uint8Array(buf));
}
function str2ab(str) {
var buf = new ArrayBuffer(str.length);
var bufView = new Uint8Array(buf);
for (var i=0, strLen=str.length; i<strLen; i++)
bufView[i] = str.charCodeAt(i);
return buf;
}
function handleQueue() {
if (!queue.length) return;
var q = queue.shift();
log(3,"Executing "+JSON.stringify(q)+" from queue");
if (q.type=="eval") uart.eval(q.expr, q.cb);
else if (q.type=="write") uart.write(q.data, q.callback, q.callbackNewline);
else log(1,"Unknown queue item "+JSON.stringify(q));
}
function log(level, s) {
if (uart.log) uart.log(level, s);
}
var endpoints = [];
var WebBluetooth = {
name : "Web Bluetooth",
description : "Bluetooth LE devices",
svg : '<svg xmlns="http://www.w3.org/2000/svg" width="48" height="48" viewBox="0 0 24 24"><path d="M0 0h24v24H0z" fill="none"/><path d="M17.71 7.71L12 2h-1v7.59L6.41 5 5 6.41 10.59 12 5 17.59 6.41 19 11 14.41V22h1l5.71-5.71-4.3-4.29 4.3-4.29zM13 5.83l1.88 1.88L13 9.59V5.83zm1.88 10.46L13 18.17v-3.76l1.88 1.88z" fill="#ffffff"/></svg>',
isSupported : function() {
if (navigator.platform.indexOf("Win")>=0 &&
(navigator.userAgent.indexOf("Chrome/54")>=0 ||
navigator.userAgent.indexOf("Chrome/55")>=0 ||
navigator.userAgent.indexOf("Chrome/56")>=0)
)
return "Chrome <56 in Windows has navigator.bluetooth but it's not implemented properly";;
if (window && window.location && window.location.protocol=="http:" &&
window.location.hostname!="localhost")
return "Serving off HTTP (not HTTPS) - Web Bluetooth not enabled";
if (navigator.bluetooth) return true;
var iOS = /iPad|iPhone|iPod/.test(navigator.userAgent) && !window.MSStream;
if (iOS) {
return "To use Web Bluetooth on iOS you'll need the WebBLE App.\nPlease go to https://itunes.apple.com/us/app/webble/id1193531073 to download it.";
} else {
return "This Web Browser doesn't support Web Bluetooth.\nPlease see https://www.espruino.com/Puck.js+Quick+Start";
}
},
connect : function(connection, callback) {
var NORDIC_SERVICE = "6e400001-b5a3-f393-e0a9-e50e24dcca9e";
var NORDIC_TX = "6e400002-b5a3-f393-e0a9-e50e24dcca9e";
var NORDIC_RX = "6e400003-b5a3-f393-e0a9-e50e24dcca9e";
var CHUNKSIZE = 20;
var btServer = undefined;
var btService;
var connectionDisconnectCallback;
var txCharacteristic;
var rxCharacteristic;
var txDataQueue = [];
var flowControlXOFF = false;
connection.close = function(callback) {
connection.isOpening = false;
if (connection.isOpen) {
connection.isOpen = false;
connection.emit('close');
} else {
if (callback) callback(null);
}
if (btServer) {
btServer.disconnect();
btServer = undefined;
txCharacteristic = undefined;
rxCharacteristic = undefined;
}
};
connection.write = function(data, callback) {
if (data) txDataQueue.push({data:data,callback:callback,maxLength:data.length});
if (connection.isOpen && !connection.txInProgress) writeChunk();
function writeChunk() {
if (flowControlXOFF) { // flow control - try again later
setTimeout(writeChunk, 50);
return;
}
var chunk;
if (!txDataQueue.length) {
uart.writeProgress();
return;
}
var txItem = txDataQueue[0];
uart.writeProgress(txItem.maxLength - txItem.data.length, txItem.maxLength);
if (txItem.data.length <= CHUNKSIZE) {
chunk = txItem.data;
txItem.data = undefined;
} else {
chunk = txItem.data.substr(0,CHUNKSIZE);
txItem.data = txItem.data.substr(CHUNKSIZE);
}
connection.txInProgress = true;
log(2, "Sending "+ JSON.stringify(chunk));
txCharacteristic.writeValue(str2ab(chunk)).then(function() {
log(3, "Sent");
if (!txItem.data) {
txDataQueue.shift(); // remove this element
if (txItem.callback)
txItem.callback();
}
connection.txInProgress = false;
writeChunk();
}).catch(function(error) {
log(1, 'SEND ERROR: ' + error);
txDataQueue = [];
connection.close();
});
}
};
navigator.bluetooth.requestDevice({
filters:[
{ namePrefix: 'Puck.js' },
{ namePrefix: 'Pixl.js' },
{ namePrefix: 'MDBT42Q' },
{ namePrefix: 'Bangle' },
{ namePrefix: 'RuuviTag' },
{ namePrefix: 'iTracker' },
{ namePrefix: 'Thingy' },
{ namePrefix: 'Espruino' },
{ services: [ NORDIC_SERVICE ] }
], optionalServices: [ NORDIC_SERVICE ]}).then(function(device) {
log(1, 'Device Name: ' + device.name);
log(1, 'Device ID: ' + device.id);
// Was deprecated: Should use getPrimaryServices for this in future
//log('BT> Device UUIDs: ' + device.uuids.join('\n' + ' '.repeat(21)));
device.addEventListener('gattserverdisconnected', function() {
log(1, "Disconnected (gattserverdisconnected)");
connection.close();
});
return device.gatt.connect();
}).then(function(server) {
log(1, "Connected");
btServer = server;
return server.getPrimaryService(NORDIC_SERVICE);
}).then(function(service) {
log(2, "Got service");
btService = service;
return btService.getCharacteristic(NORDIC_RX);
}).then(function (characteristic) {
rxCharacteristic = characteristic;
log(2, "RX characteristic:"+JSON.stringify(rxCharacteristic));
rxCharacteristic.addEventListener('characteristicvaluechanged', function(event) {
var dataview = event.target.value;
if (uart.flowControl) {
for (var i=0;i<dataview.length;i++) {
var ch = dataview.getUint8(i);
if (ch==17) { // XON
log(2,"XON received => resume upload");
flowControlXOFF = false;
}
if (ch==19) { // XOFF
log(2,"XOFF received => pause upload");
flowControlXOFF = true;
}
}
}
var str = ab2str(dataview.buffer);
log(3, "Received "+JSON.stringify(str));
connection.emit('data', str);
});
return rxCharacteristic.startNotifications();
}).then(function() {
return btService.getCharacteristic(NORDIC_TX);
}).then(function (characteristic) {
txCharacteristic = characteristic;
log(2, "TX characteristic:"+JSON.stringify(txCharacteristic));
}).then(function() {
connection.txInProgress = false;
connection.isOpen = true;
connection.isOpening = false;
isBusy = false;
queue = [];
callback(connection);
connection.emit('open');
// if we had any writes queued, do them now
connection.write();
}).catch(function(error) {
log(1, 'ERROR: ' + error);
connection.close();
});
return connection;
}
};
var WebSerial = {
name : "Web Serial",
description : "USB connected devices",
svg : '<svg xmlns="http://www.w3.org/2000/svg" width="48" height="48" viewBox="0 0 24 24"><path d="M0 0h24v24H0z" fill="none"/><path d="M15 7v4h1v2h-3V5h2l-3-4-3 4h2v8H8v-2.07c.7-.37 1.2-1.08 1.2-1.93 0-1.21-.99-2.2-2.2-2.2-1.21 0-2.2.99-2.2 2.2 0 .85.5 1.56 1.2 1.93V13c0 1.11.89 2 2 2h3v3.05c-.71.37-1.2 1.1-1.2 1.95 0 1.22.99 2.2 2.2 2.2 1.21 0 2.2-.98 2.2-2.2 0-.85-.49-1.58-1.2-1.95V15h3c1.11 0 2-.89 2-2v-2h1V7h-4z" fill="#ffffff"/></svg>',
isSupported : function() {
if (!navigator.serial)
return "No navigator.serial - Web Serial not enabled";
if (window && window.location && window.location.protocol=="http:" &&
window.location.hostname!="localhost")
return "Serving off HTTP (not HTTPS) - Web Serial not enabled";
return true;
},
connect : function(connection, callback) {
var serialPort;
function disconnected() {
connection.isOpening = false;
if (connection.isOpen) {
log(1, "Disconnected");
connection.isOpen = false;
connection.emit('close');
}
}
// TODO: Pass USB vendor and product ID filter when supported by Chrome.
navigator.serial.requestPort({}).then(function(port) {
log(1, "Connecting to serial port");
serialPort = port;
return port.open({ baudrate: 115200 });
}).then(function () {
function readLoop() {
var reader = serialPort.readable.getReader();
reader.read().then(function ({ value, done }) {
reader.releaseLock();
if (value) {
var str = ab2str(value.buffer);
log(3, "Received "+JSON.stringify(str));
connection.emit('data', str);
}
if (done) {
disconnected();
} else {
readLoop();
}
});
}
readLoop();
log(1,"Serial connected. Receiving data...");
connection.txInProgress = false;
connection.isOpen = true;
connection.isOpening = false;
callback(connection);
}).catch(function(error) {
log(0, 'ERROR: ' + error);
disconnected();
});
connection.close = function(callback) {
if (serialPort) {
serialPort.close();
serialPort = undefined;
}
disconnected();
};
connection.write = function(data, callback) {
var writer = serialPort.writable.getWriter();
// TODO: progress?
writer.write(str2ab(data)).then(function() {
callback();
}).catch(function(error) {
log(0,'SEND ERROR: ' + error);
closeSerial();
});
writer.releaseLock();
};
return connection;
}
};
// ======================================================================
endpoints.push(WebBluetooth);
endpoints.push(WebSerial);
// ======================================================================
var connection;
function connect(callback) {
var connection = {
on : function(evt,cb) { this["on"+evt]=cb; },
emit : function(evt,data) { if (this["on"+evt]) this["on"+evt](data); },
isOpen : false,
isOpening : true,
txInProgress : false
};
// modal
var e = document.createElement('div');
e.style = 'position:absolute;top:0px;left:0px;right:0px;bottom:0px;opacity:0.5;z-index:100;background:black;';
// menu
var menu = document.createElement('div');
menu.style = 'position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);font-family: Sans-Serif;z-index:101;';
var menutitle = document.createElement('div');
menutitle.innerText = "SELECT A PORT...";
menutitle.style = 'color:#fff;background:#000;padding:8px 8px 4px 8px;font-weight:bold;';
menu.appendChild(menutitle);
var items = document.createElement('div');
items.style = 'color:#000;background:#fff;padding:4px 8px 4px 8px;';
menu.appendChild(items);
endpoints.forEach(function(endpoint) {
var supported = endpoint.isSupported();
if (supported!==true)
log(0, endpoint.name+" not supported, "+supported);
var ep = document.createElement('div');
ep.style = 'width:300px;height:60px;background:#ccc;margin:4px 0px 4px 0px;padding:0px 0px 0px 68px;cursor:pointer;';
ep.innerHTML = '<div style="position:absolute;left:8px;width:48px;height:48px;background:#999;padding:6px;cursor:pointer;">'+endpoint.svg+'</div>'+
'<div style="font-size:150%;padding-top:8px;">'+endpoint.name+'</div>'+
'<div style="font-size:80%;color:#666">'+endpoint.description+'</div>';
ep.onclick = function(evt) {
connection = endpoint.connect(connection, callback);
evt.preventDefault();
document.body.removeChild(menu);
document.body.removeChild(e);
};
items.appendChild(ep);
});
document.body.appendChild(e);
document.body.appendChild(menu);
return connection;
}
function checkIfSupported() {
var anySupported = false;
endpoints.forEach(function(endpoint) {
var supported = endpoint.isSupported();
if (supported===true)
anySupported = true;
else
log(0, endpoint.name+" not supported, "+supported);
});
return anySupported;
}
// ======================================================================
/* convenience function... Write data, call the callback with data:
callbackNewline = false => if no new data received for ~0.2 sec
callbackNewline = true => after a newline */
function write(data, callback, callbackNewline) {
if (!checkIfSupported()) return;
if (isBusy) {
log(3, "Busy - adding write to queue");
queue.push({type:"write", data:data, callback:callback, callbackNewline:callbackNewline});
return;
}
var cbTimeout;
function onWritten() {
if (callbackNewline) {
connection.cb = function(d) {
var newLineIdx = connection.received.indexOf("\n");
if (newLineIdx>=0) {
var l = connection.received.substr(0,newLineIdx);
connection.received = connection.received.substr(newLineIdx+1);
connection.cb = undefined;
if (cbTimeout) clearTimeout(cbTimeout);
cbTimeout = undefined;
if (callback)
callback(l);
isBusy = false;
handleQueue();
}
};
}
// wait for any received data if we have a callback...
var maxTime = 300; // 30 sec - Max time we wait in total, even if getting data
var dataWaitTime = callbackNewline ? 100/*10 sec if waiting for newline*/ : 3/*300ms*/;
var maxDataTime = dataWaitTime; // max time we wait after having received data
cbTimeout = setTimeout(function timeout() {
cbTimeout = undefined;
if (maxTime) maxTime--;
if (maxDataTime) maxDataTime--;
if (connection.hadData) maxDataTime=dataWaitTime;
if (maxDataTime && maxTime) {
cbTimeout = setTimeout(timeout, 100);
} else {
connection.cb = undefined;
if (callbackNewline)
log(2, "write waiting for newline timed out");
if (callback)
callback(connection.received);
isBusy = false;
handleQueue();
connection.received = "";
}
connection.hadData = false;
}, 100);
}
if (connection && (connection.isOpen || connection.isOpening)) {
if (!connection.txInProgress) connection.received = "";
isBusy = true;
return connection.write(data, onWritten);
}
connection = connect(function(uart) {
if (!uart) {
connection = undefined;
if (callback) callback(null);
return;
}
connection.received = "";
connection.on('data', function(d) {
connection.received += d;
connection.hadData = true;
if (connection.cb) connection.cb(d);
});
connection.on('close', function(d) {
connection = undefined;
});
isBusy = true;
connection.write(data, onWritten);
});
}
function evaluate(expr, cb) {
if (!checkIfSupported()) return;
if (isBusy) {
log(3, "Busy - adding eval to queue");
queue.push({type:"eval", expr:expr, cb:cb});
return;
}
write('\x10eval(process.env.CONSOLE).println(JSON.stringify('+expr+'))\n', function(d) {
try {
var json = JSON.parse(d.trim());
cb(json);
} catch (e) {
log(1, "Unable to decode "+JSON.stringify(d)+", got "+e.toString());
cb(null, "Unable to decode "+JSON.stringify(d)+", got "+e.toString());
}
}, true/*callbackNewline*/);
};
// ----------------------------------------------------------
var uart = {
/// Are we writing debug information? 0 is no, 1 is some, 2 is more, 3 is all.
debug : 3,//FIXME 1,
/// Should we use flow control? Default is true
flowControl : true,
/// Used internally to write log information - you can replace this with your own function
log : function(level, s) { if (level <= this.debug) console.log("<UART> "+s)},
/// Called with the current send progress or undefined when done - you can replace this with your own function
writeProgress : function (charsSent, charsTotal) {
//console.log(charsSent + "/" + charsTotal);
},
/** Connect to a new device - this creates a separate
connection to the one `write` and `eval` use. */
connect : connect,
/// Write to a device and call back when the data is written. Creates a connection if it doesn't exist
write : write,
/// Evaluate an expression and call cb with the result. Creates a connection if it doesn't exist
eval : evaluate,
/// Write the current time to the device
setTime : function(cb) {
var d = new Date();
var cmd = 'setTime('+(d.getTime()/1000)+');';
// in 1v93 we have timezones too
cmd += 'if (E.setTimeZone) E.setTimeZone('+d.getTimezoneOffset()/-60+');\n';
write(cmd, cb);
},
/// Did `write` and `eval` manage to create a connection?
isConnected : function() {
return connection!==undefined;
},
/// get the connection used by `write` and `eval`
getConnection : function() {
return connection;
},
/// Close the connection used by `write` and `eval`
close : function() {
if (connection)
connection.close();
},
/** Utility function to fade out everything on the webpage and display
a window saying 'Click to continue'. When clicked it'll disappear and
'callback' will be called. This is useful because you can't initialise
Web Bluetooth unless you're doing so in response to a user input.*/
modal : function(callback) {
var e = document.createElement('div');
e.style = 'position:absolute;top:0px;left:0px;right:0px;bottom:0px;opacity:0.5;z-index:100;background:black;';
e.innerHTML = '<div style="position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);font-family: Sans-Serif;font-size:400%;color:white;">Click to Continue...</div>';
e.onclick = function(evt) {
callback();
evt.preventDefault();
document.body.removeChild(e);
};
document.body.appendChild(e);
}
};
return uart;
}));