CC3000.md

CC3000 WiFi Module

• KEYWORDS: Wireless,CC3000,CC 3000,WiFi,Internet,WLAN,Web Server,HTTP,Built-In

The Espruino Board supports the Texas Instruments CC3000 WiFi module. This allows you to connect to Wireless networks (and hence the internet).

First off, you need to connect the module. Currently it must be on the following pins:

CC3000	Espruino
GND	GND
3v3	Do not use
VIN	VBAT
CLK/SCK	B3
DOUT/MISO	B4
DIN/MOSI	B5
CS	B6
EN/VBEN	B7
IRQ	B8

Note: The voltage regulator on the Adafruit CC3000 module will work with voltages as high as 18V on VIN. If using a different breakout board, you must be sure that the voltage applied to the CC3000 (Vcc) is between 2.7 and 4.8v. On the Espruino Board, VBAT is 4.3v when running from USB and is the same as the battery voltage when plugged into a battery.

Using the CC3000 is as follows:

• Connect it as above CC3000
• Load the CC3000 module with require("CC3000").connect(). This returns a WLAN object.
• Call connect on that object (see the example below), with a callback function
• In the callback function, respond to the dhcp message and use the http module to access the internet

Note: Some calls to the CC3000 module will take a second or more to return, due to TI's driver. connect especially takes several seconds. In order to make sure your code uploads properly (and that you can save your code to flash), the code to initialise the CC3000 should be put inside a function called onInit. Execute onInit() manually on the left-hand side after uploading, or type save() to save your code to Flash and run it.

This example loads a webpage and prints the result:

var wlan = require("CC3000").connect();
wlan.connect( "AccessPointName", "WPA2key", function (s) { 
  if (s=="dhcp") {
    require("http").get("http://www.pur3.co.uk/hello.txt", function(res) {
      res.on('data', function(data) {
        console.log(">" + data);
      });
    });
  }
});

Note: that we're putting all the network initialisation in the callback. The CC3000 will occasionally disconnect (or will sometimes crash and have to be automatically rebooted) and any active HTTP servers or clients will get removed. When it reconnects the callback will be called with s=='dhcp' and you can re-add them. Your code needs to be able to cope with the fact that it may be called more than once (eg. if you use setInterval make sure you use clearInterval to clear the old interval first).

Custom Pins

Calling require("CC3000").connect() without arguments will use the default pins shown above, but you can use a custom SPI device and pins by specifying them as follows:

SPI1.setup({ sck:B3, miso:B4, mosi:B5, baud:1000000, mode:1});
var wlan = require("CC3000").connect(SPI1, B6 */ CS */, B7 /* EN */, B8 /* IRQ */);

Note: It's very important that SPI mode is set to 1, or the CC3000 will not be able to initialise.

Disconnecting

You can also call wlan.disconnect() which will turn the CC3000 off completely. This is very useful if you're running off a battery and want to connect to the internet, send data, and then disconnect.

You could use it like this:

var wlan = require("CC3000").connect();

function getTime() {
  // if we don't get DHCP or a complete request in 30 seconds,
  // disconnect
  var failTimeout = setTimeout(function() {
    console.log("Timed out, disconnecting...");
    wlan.disconnect();
  }, 30000);
  wlan.connect( "AccessPointName", "WPA2key", function (s) {
    if (s=="dhcp") {
      require("http").get("http://www.pur3.co.uk/time.php",
                          function(res) {
        // store the result
        var result = "";
        res.on('data', function(data) {
          result += data;
          console.log(data);
        });
        /* When the connection closes, print what we
        got, and then disconnect from WiFi */
        res.on('close', function() {
          console.log("Got: "+result);
          // finished, disconnect anyway
          setTimeout(function() {
            clearTimeout(failTimeout);
            console.log("Complete!, disconnecting...");
            wlan.disconnect();
          },1000);
        });
      });
    }
  });
}

// Every 24 hours, get the time again
setInterval(getTime, 24*60*60*1000);

Web Server

Creating a Web Server is easy too:

var wlan = require("CC3000").connect();
wlan.connect( "AccessPointName", "WPA2key", function (s) { 
  if (s=="dhcp") {
    console.log("My IP is "+wlan.getIP().ip);
    require("http").createServer(function (req, res) {
      res.writeHead(200, {'Content-Type': 'text/plain'});
      res.write('Hello World');
      res.end();
    }).listen(80);
  }
});

When the CC3000 connects to your network, it'll output My IP is 1.2.3.4. If you then go to http://1.2.3.4 with your web browser, you'll see a webpage saying Hello World.

If you want to do something a bit more interesting, you can turn lights on and off and view the status of inputs:

function onPageRequest(req, res) {
  var a = url.parse(req.url, true);
  res.writeHead(200, {'Content-Type': 'text/html'});
  res.write('<html><body>');
  res.write('<p>Pin is '+(BTN.read()?'on':'off')+'</p>');
  res.write('<a href="?led=1">on</a><br/><a href="?led=0">off</a>');
  res.end('</body></html>');
  if (a.query && "led" in a.query) digitalWrite(LED1, a.query["led"]);
}

var wlan = require("CC3000").connect();
wlan.connect( "AccessPointName", "WPA2key", function (s) { 
  if (s=="dhcp") {
    console.log("My IP is "+wlan.getIP().ip);
    require("http").createServer(onPageRequest).listen(80);
  }
});

Note that to read the state of the button with this example, you'll have to press the button down and then press refresh in your web browser. Turning the LED on and off is done by loading a webpage with a certain name.

For more examples, please see the [[Internet]] page.

Using

• APPEND_USES: CC3000

Buying

At the moment the only CC3000 module that we know works for sure is the AdaFruit CC3000 module, so we'd recommend that you get this from AdaFruit or one of their distributors.

The Embedded Adventures module has been tested and does not currently work with Espruino. If you have success with it, please let us know!