How to configure Linux to act as a Bluetooth RFCOMM SPP server?

Question

I'm writing a phone app for Android that connects to a bluetooth RFCOMM device in my car. My phone app talks AT commands with it. For development work, I often need to communicate with the device to try different commands and things.

My neighbors are starting to think I'm weird because I sit in my car for hours on end with my laptop screen shining on my face, typing away like a script kiddie.

I'd much rather configure one of my many Linux servers to act as a bluetooth RFCOMM device and allow me to connect to it (indoors, while I sit on my couch).

I imagine I have to start with something like sdptool add SP

But then what?

I'm perfectly happy writing a perl app to handle the I/O, but I just don't know how to make the bluez stack accept connections and subsequently pipe that stream to a perl app.

Answer 1

Using Perl Net::Bluetooth looks promising... I'm playing with the following code, mostly copy and pasted from the examples, and cobbled together from various sources.

cat rfcomm-fake-server.pl

#! /usr/bin/perl -w

# Information Sources: 
# http://search.cpan.org/~iguthrie/Net-Bluetooth-0.40/Bluetooth.pm
# http://people.csail.mit.edu/albert/bluez-intro/x290.html#py-rfcomm-server-sdp
# http://people.csail.mit.edu/albert/bluez-intro/x232.html#rfcomm-server.py
# http://linuxdevcenter.com/pub/a/linux/2006/09/21/rediscovering-bluetooth.html?page=last


  use Net::Bluetooth;

  #### create a RFCOMM server

print "create rfcomm server\n";

  $obj = Net::Bluetooth->newsocket("RFCOMM");
  #### bind to port 1

print "binding to port 1\n";
  if($obj->bind(1) != 0) {
        die "bind error: $!\n";
  }

print "listening with backlog 2\n";
  #### listen with a backlog of 2
  if($obj->listen(2) != 0) {
        die "listen error: $!\n";
  }

print "register UUID\n";
  #### register a service
  #### $obj must be a open and bound socket
  # UUID Format: 00000000-0000-0000-0000-000000000000
  # RFCOMM:      00001101-0000-1000-8000-00805F9B34FB
  my $service_obj = Net::Bluetooth->newservice($obj, "00001101-0000-1000-8000-00805F9B34FB", "FAKEOBD", "Fake OBD Adapter");
print "Now what?\n";
  unless(defined($service_obj)) {
    print "There was a problem registering the UUID...\n";
    die ("Couldn't register UUID/service");
        #### couldn't register service
  }

  #### accept a client connection
print "Blocking until we receive an incoming connection";
  $client_obj = $obj->accept();
  unless(defined($client_obj)) {
        die "client accept failed: $!\n";
  }

  #### get client information
  my ($caddr, $port) = $client_obj->getpeername();

  print "Connected to $caddr on port $port\n";

  #### create a Perl filehandle for reading and writing
  *CLIENT = $client_obj->perlfh();
  print CLIENT "Hello there?";

while (<CLIENT>) {
    print "Data: "
}

Answer 2

I tried the Perl Script by regulatre, but couldn't get it to work. The problem is that the Net::Bluetooth module doesn't register the class correctly with SDP.

Finally, I found this Java example that worked perfectly:

http://www.jsr82.com/jsr-82-sample-spp-server-and-client/

Note that it requires you to install the BlueCove jars on Linux. If your linux has the "bluez" stack, then you will need the two jars from BlueCove called

• bluecove-version.jar
• bluecove-gpl-version.jar