Making Things Talk

WIRELESS COMMUNICATION 213

void blink(int howManyTimes) {

for (int i=0; i< howManyTimes; i++) {

digitalWrite(txLed, HIGH);

delay(200);

digitalWrite(txLed, LOW);

delay(200);

}

}

The blink() method is the same as

it was in the earlier XBee example:

8

void loop() {

if (Serial.available() > 0) {

// signal that there's incoming data using the rx LED:

digitalWrite(rxLed, HIGH);

// do something with the incoming byte:

handleSerial();

// turn the rx LED off.

digitalWrite(rxLed, LOW);

}

// if you're not connected and 5 seconds have passed in that state,

// make an attempt to connect to the other radio:

if (!connected && millis() - lastConnectTry > connectTimeout) {

BTConnect();

lastConnectTry = millis();

}

}

The main loop listens for incoming

serial data and handles it. If more than

five seconds have passed and the

radio’s still not connected to the other

radio, the microcontroller attempts to

connect again:

8

The handleSerial() method is similar to the

one in the XBee project, but there are some

important differences. First, because there’s a dedicated

connection between the two radios, you need to keep track

of the connection status. When a new connection is made,

the BlueSMiRF will send a serial message like this before

dropping into data mode:

CONNECT,0016CB202BF3

When the connection’s broken, it will send this message,

and stay in command mode: ...