About tunnel.py again

GNU Radio
1

I’m trying to connect two computers  using tunnel.py example but it
fails with a message uOBBBB, I’m working with Ubuntu
9.04, openSUSE 11.1 and GNU radio 3.2.2. Everything was fine when I did
it with GNU radio 3.1.3 and both computers with openSUSE 11.1Please can
somebody tell me what BBBB means?

JhonQ

2

On Tue, May 25, 2010 at 10:03:32AM -0700, Juan Q. wrote:

I’m trying to connect two computers using tunnel.py example but it fails with a message uOBBBB, I’m working with Ubuntu
9.04, openSUSE 11.1 and GNU radio 3.2.2. Everything was fine when I did
it with GNU radio 3.1.3 and both computers with openSUSE 11.1Please can somebody tell me what BBBB means?

JhonQ

A quick look at the code reveals that it means that the transmitter
has backed off because it detected carrier.

    while 1:
        payload = os.read(self.tun_fd, 10*1024)
        if not payload:
            self.tb.send_pkt(eof=True)
            break

        if self.verbose:
            print "Tx: len(payload) = %4d" % (len(payload),)

        delay = min_delay
        while self.tb.carrier_sensed():
            sys.stderr.write('B')
            time.sleep(delay)
            if delay < 0.050:
                delay = delay * 2       # exponential back-off

        self.tb.send_pkt(payload)

Try changing the carrier threshold using the -c command line option.

Eric