On 08/23/2013 09:03 PM, Kapil Borle wrote:
Hi,
I am trying to run benchmark_rx.py and the first time I execute it
after booting up the PC, I encounter the error pasted at the end of
this message. The error goes away when I try to run benchmark_rx
again, but comes back again after rebooting and executing bechmark_rx.
Some information about the PC
~$ uname -a
Linux ubuntu 3.5.0-23-generic #35~precise1-Ubuntu SMP Fri Jan 25
17:13:26 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
~$ lsb_release -a
No LSB modules are available.
Distributor ID:Ubuntu
Description:Ubuntu 12.04.3 LTS
Release:12.04
Codename:precise
~$ gnuradio-config-info -v
v3.7.0-104-g6bf21a5a
Thanks,
Kapil
*Error Message:*
~$
/usr/local/share/gnuradio/examples/digital/narrowband/benchmark_rx.py
-m dbpsk -r 500000 -f 0.6e9 -a addr=192.168.10.2 --spec=A:0 -A TX/RX
--rx-gain=20 -v -S 2
linux; GNU C++ version 4.6.3; Boost_104800; UHD_003.005.001-0-gf3a16983
Using Volk machine: avx_64_mmx
Demodulator:
bits per symbol: 1
RRC roll-off factor: 0.35
FLL bandwidth: 6.28e-02
Timing bandwidth: 6.28e-02
Phase bandwidth: 6.28e-02
-- Opening a USRP2/N-Series device...
-- Current recv frame size: 1472 bytes
-- Current send frame size: 756 bytes
UHD Error:
Control packet attempt 0, sequence number 1:
RuntimeError: no control response, possible packet loss
UHD Error:
Control packet attempt 1, sequence number 2:
RuntimeError: no control response, possible packet loss
UHD Error:
Control packet attempt 2, sequence number 3:
RuntimeError: no control response, possible packet loss
Traceback (most recent call last):
File
"/usr/local/share/gnuradio/examples/digital/narrowband/benchmark_rx.py",
line 141, in <module>
main()
File
"/usr/local/share/gnuradio/examples/digital/narrowband/benchmark_rx.py",
line 130, in main
tb = my_top_block(demods[options.modulation], rx_callback, options)
File
"/usr/local/share/gnuradio/examples/digital/narrowband/benchmark_rx.py",
line 57, in __init__
options.verbose)
File
"/usr/local/share/gnuradio/examples/digital/narrowband/uhd_interface.py",
line 190, in __init__
freq, gain, spec, antenna)
File
"/usr/local/share/gnuradio/examples/digital/narrowband/uhd_interface.py",
line 52, in __init__
self.u = uhd.usrp_source(device_addr=args,
stream_args=uhd.stream_args('fc32'))
File
"/usr/local/lib/python2.7/dist-packages/gnuradio/uhd/__init__.py",
line 121, in constructor_interceptor
return old_constructor(*args)
File
"/usr/local/lib/python2.7/dist-packages/gnuradio/uhd/uhd_swig.py",
line 1699, in make
return _uhd_swig.usrp_source_make(*args)
RuntimeError: RuntimeError: link dead: timeout waiting for control
packet ACK
Thanks,
Kapil
This may just be an ARP issue. When you first boot, there's no ARP
cache entry for the USRP, so ARP has to run, and it may be that your IP
stack is
configured to drop packets that arrive at the interface during ARP
negotiation, rather than holding them. Just a guess.
With TCP, this isn't as big an issue, because TCP has a retry
mechanism. For UDP protocols (which UHD uses) this could be an issue.
_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
