Examples - Hello
This is a basic example sending two XBee frames: one with a hello content and another one with world!
Those two XBee frames are broadcasted to all XBee modules.
This simple example allows to check your local XBee module settings.
Build
First make sure you have built the project. Next, if you have a look at the examples/hello/target/appassembler directory, you will find a complete distribution of the example.
Configure
A few settings are required in order to get the gateway to run properly. If you launch xbee-hello with no arguments, the usage will be displayed.
Here is below a list of the parameters:
| CLI arg | Description |
|---|---|
| -b | Bauds (optional, by default 9600) |
| serial port | Serial port to use: one Windows something like COM3, on Unix machines something like /dev/tty.usbmodem123 |
Run
Depending on your OS you either need to run sh bin/xbee-hello or bin\xbee-hello.bat. Do not forget the required CLI parameters for this example to work.
Understand
This library provides you a Netty handler which is able to encode XBeeRequest objects as expected by the XBee module (using API mode).
So in order to send some basic broadcasted messages, you simply need to write a Netty handler which encodes String objects into XBeeTransmit16 objects:
public class XBeeHelloEncoder extends MessageToMessageEncoder<String> {
@Override
protected Object encode(ChannelHandlerContext ctx, String msg) throws Exception {
return new XBeeTransmit16(XBeeFrameIdGenerator.nextFrameID(),
XBeeAddress16.BROADCAST,
new XBeeTransmit.Options(false, false),
msg.getBytes("UTF-8"));
}
}
The way to use this encoder can be illustrated here. You simply write String objects in Netty channel and your Netty handler will convert them to XBeeRequest objects:
Bootstrap b = new Bootstrap();
b.group(new OioEventLoopGroup())
.channel(RxtxChannel.class)
.remoteAddress(new RxtxDeviceAddress(serialPort)
.option(RxtxChannelOption.BAUD_RATE, baudRate)
.handler(new ChannelInitializer<RxtxChannel>() {
@Override
public void initChannel(RxtxChannel ch) throws Exception {
ChannelPipeline pipeline = ch.pipeline();
pipeline.addLast("xbee-request-encoder", new XBeeRequestEncoder());
pipeline.addLast("xbee-hello-encoder", new XBeeHelloEncoder());
[...]
}
});
ChannelFuture f = b.connect().sync();
[...]
Channel channel = f.channel();
channel.write("hello\n");
channel.write("world!\n");
// wait a little bit for messages to be sent
Thread.sleep(5000);
channel.closeFuture().sync();