Kernel freeze during continuous transmission using USRP2

GNU Radio
1

Hi,

I am using ucla-zigbee stack for continuously transmitting a fixed
symbol (all zeroes) for 802.15.4.
I finally made it to work on USRP2 with RFX2400, but now my machine’s
kernel freezes after 5~10 minutes (even no ping responses). Basically,
using sig_source I generate a stream of a constant 0’s, and feed it to
802.15.4 modulator to transmit O-QPSK signal.

When I do packetized transmissions once a second, I do not see the
freezing problem. I only see this when I continuously transmit.

Does anyone has any clue/suggestion? I am using Ubuntu 8.04 with the
kernel 2.6.24-21, and using D-Link DGE-560T gigabit pci-express adapter.
Thanks,
Jung Il Choi

2

On 12/21/2009 03:31 PM, Jung Il Choi wrote:

freezing problem. I only see this when I continuously transmit.

Does anyone has any clue/suggestion? I am using Ubuntu 8.04 with the
kernel 2.6.24-21, and using D-Link DGE-560T gigabit pci-express adapter.
Thanks,
Jung Il Choi

I’ve never seen this happen. You are using a pretty old kernel and
distribution, so you might try upgrading.

Matt

3

On Mon, 2009-12-21 at 15:31 -0800, Jung Il Choi wrote:

Does anyone has any clue/suggestion? I am using Ubuntu 8.04 with the
kernel 2.6.24-21, and using D-Link DGE-560T gigabit pci-express adapter.

I had the same problem (same card) on Ubuntu 8.10. I have since
upgraded to 9.10, and rebuilt GR (just in case), and I haven’t had
another hang yet.

–ETS

4

I installed 9.10, and I think now the hanging problem is gone. It’s been
running for about an hour.
I guess it was some driver issue.

Thank you very much!
Jung Il

5

There’s no switch between the machine and USRP2.
I did ethtool, and it was on for all three. When TX is disabled,
strangely I am seeing a slower speed leaving some gaps between signals.

Thanks!

Jung Il

6

On Mon, Dec 21, 2009 at 03:31:23PM -0800, Jung Il Choi wrote:

When I do packetized transmissions once a second, I do not see the
freezing problem. I only see this when I continuously transmit.

Does anyone has any clue/suggestion? I am using Ubuntu 8.04 with the
kernel 2.6.24-21, and using D-Link DGE-560T gigabit pci-express
adapter.
Thanks,
Jung Il Choi

Is there a switch between your machine and the USRP2?

If you type

$ ethtool -a eth0

what does it display? (assuming eth0 is the interface the usrp2 is
connected to)

I would expect:

$ ethtool -a eth1
Pause parameters for eth1:
Autonegotiate: on
RX: on
TX: off

Eric