Transmit Data Using Bluetooth Communication

You can read and write both text data (ASCII based) and binary data. For text data, use the readline and writeline functions. For binary data, use the read and write functions.

In this example, a LEGO^® MINDSTORMS^® NXT robot with the name C3PO is connected to the computer. Communicate with the NXT device by following these steps.

1. Determine what Bluetooth^® devices are accessible from your computer.

   bluetoothlist

   ans =
   
     4×4 table
   
           Name            Address        Channel          Status      
       _____________    ______________    _______    __________________
   
       "C3PO"           "0016530FD63D"    1          "Ready to connect"         
       "HC-06"          "98D331FB3B77"    1          "Requires pairing"
       "mjin-maci"      "A886DDA44062"    3          "Requires pairing"
       "DMTDevice"      "B0B448F47A4C"    Unknown    "Unknown"         
   
   

2. In this case, C3PO is the device name of the NXT robot and is shown in the output. To connect to the device, create a Bluetooth object called bt using channel 1 of the NXT device.

   bt = bluetooth("C3PO",1);

   bt = 
   
     bluetooth with properties:
   
                    Name: "C3PO"
                 Address: "0016530FD63D"
                 Channel: 1
       NumBytesAvailable: 0
         NumBytesWritten: 0
   
     Show all properties
   
   

3. Send a message to the remote device using the write function. In this example, specific characters are sent to the device that this particular device (the NXT robot C3PO) understands. You can write to the device and then view the NumBytesWritten property to check that the values were sent.

   write(bt,[2,0,1,155])
   bt.NumBytesWritten

   ans =
   
        35

   You can see that the 35 bytes of data have been written to the device.

4. View the NumBytesAvailable property to see the number of bytes available to read.

   bt.NumBytesAvailable

   ans =
   
        35

   Use the read function to read 35 bytes from the remote device.

   name = read(bt,35);
   char(name(7:10))

   ans =
   
       'C3PO'

   The device returns the characters 'C3PO', which is the name of the device. That was a reply to the instructions that were sent to it. See the documentation for your device for this type of device-specific communication information.

5. Clean up by clearing the object.

   clear bt

Other Functionality

The following functions can be used with the Bluetooth object.

read	Read data from Bluetooth device
readline	Read line of ASCII string data from Bluetooth device
write	Write data to Bluetooth device
writeline	Write line of ASCII data to Bluetooth device
configureTerminator	Set terminator for ASCII string communication with Bluetooth device
configureCallback	Set callback function and trigger condition for communication with Bluetooth device
flush	Clear Bluetooth device buffers