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Today's Topics:
1. E100 issue (Nowlan, Sean)
2. Downconversion of CW to Baseband (Brian Heilig)
3. Re: Downconversion of CW to Baseband (Nick Foster)
4. Re: Downconversion of CW to Baseband (Brian Heilig)
5. Re: E100 issue (Philip Balister)
6. Re: Error on the page UHD_Linux (Josh Blum)
7. Re: E100 issue (Ben Hilburn)
8. Re: E100 issue (Nowlan, Sean)
9. Re: E100 issue (Ben Hilburn)
10. Re: FPGA and FW update of N210 (Farhad Abdolian)
11. Re: FPGA and FW update of N210 (Josh Blum)
12. Re: FPGA and FW update of N210 (Orkhan Badirkhanli)
13. Dropped data (Knee, Peter A)
14. Re: Dropped data (Josh Blum)
----------------------------------------------------------------------
Message: 1
Date: Thu, 5 Apr 2012 16:53:52 +0000
From: "Nowlan, Sean" <[email protected]>
To: "[email protected]" <[email protected]>
Subject: [USRP-users] E100 issue
Message-ID: <195933287DC65748BA7AE867BA8E430B62176E97@apatlisdmbx02>
Content-Type: text/plain; charset="us-ascii"
I used the Ettus make script to build the latest master image (e1xx-003) on the
4GB SD card that came with the E100. After booting it up, I don't get any
output from the console, and the Ethernet lights show no life when I plug in a
good cable. Status lights "D" and "F" are lit, but none of the others light up
during boot. Any thoughts?
Thanks,
Sean
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Message: 2
Date: Thu, 5 Apr 2012 13:55:21 -0400
From: Brian Heilig <[email protected]>
To: [email protected]
Subject: [USRP-users] Downconversion of CW to Baseband
Message-ID:
<CALLWv_m3ijuBHEDstHvkPvrdU7PhYYmJdQdK2vs=unzb04+...@mail.gmail.com>
Content-Type: text/plain; charset="iso-8859-1"
Dear list,
I have a question that might be USRP related, but is more likely an RF
engineering question.
I have a signal generator that I tuned to 900 MHz CW. I apply this
unmodulated carrier to the USRP2, which I have configured to downconvert
this signal using a 900 MHz reference. Both the USRP and signal generator
are disciplined to the same reference. What I expected to see at the output
of the A2D (before any DC correction within the FPGA) is a DC signal with
noise on both I and Q. I expected that the atan of -Q/I (summed over some
interval to reduce noise) would provide the phase angle of the received CW,
which would be constant. Instead I received noise.
According to the USRP2 schematic there are no capacitors in series between
the mixer and the A2D. And I'm viewing the samples before any DC removal
logic in the FPGA.
Is there something obvious I'm missing? Are my assumptions correct?
Thanks,
Brian
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Message: 3
Date: Thu, 5 Apr 2012 11:25:59 -0700
From: Nick Foster <[email protected]>
To: Brian Heilig <[email protected]>
Cc: [email protected]
Subject: Re: [USRP-users] Downconversion of CW to Baseband
Message-ID:
<calalhjvfeosia9kbggm65t+m_az7kh7dvcjegxnrac1wryf...@mail.gmail.com>
Content-Type: text/plain; charset="iso-8859-1"
On Thu, Apr 5, 2012 at 10:55 AM, Brian Heilig <[email protected]>wrote:
> Dear list,
>
> I have a question that might be USRP related, but is more likely an RF
> engineering question.
>
> I have a signal generator that I tuned to 900 MHz CW. I apply this
> unmodulated carrier to the USRP2, which I have configured to downconvert
> this signal using a 900 MHz reference. Both the USRP and signal generator
> are disciplined to the same reference. What I expected to see at the output
> of the A2D (before any DC correction within the FPGA) is a DC signal with
> noise on both I and Q. I expected that the atan of -Q/I (summed over some
> interval to reduce noise) would provide the phase angle of the received CW,
> which would be constant. Instead I received noise.
>
> According to the USRP2 schematic there are no capacitors in series between
> the mixer and the A2D. And I'm viewing the samples before any DC removal
> logic in the FPGA.
>
> Is there something obvious I'm missing? Are my assumptions correct?
>
Which daughterboard are you using?
--n
>
> Thanks,
> Brian
>
>
> _______________________________________________
> USRP-users mailing list
> [email protected]
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
>
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Message: 4
Date: Thu, 5 Apr 2012 14:30:43 -0400
From: Brian Heilig <[email protected]>
To: Nick Foster <[email protected]>
Cc: [email protected]
Subject: Re: [USRP-users] Downconversion of CW to Baseband
Message-ID:
<CALLWv_=bkjcfmudbwqcf2bj2wp0wp2hrjxgbpiadmdz5qe4...@mail.gmail.com>
Content-Type: text/plain; charset="iso-8859-1"
The daughterboard is an rfx900. Sorry for excluding that detail.
On Thu, Apr 5, 2012 at 2:25 PM, Nick Foster <[email protected]> wrote:
> On Thu, Apr 5, 2012 at 10:55 AM, Brian Heilig <[email protected]>wrote:
>
>> Dear list,
>>
>> I have a question that might be USRP related, but is more likely an RF
>> engineering question.
>>
>> I have a signal generator that I tuned to 900 MHz CW. I apply this
>> unmodulated carrier to the USRP2, which I have configured to downconvert
>> this signal using a 900 MHz reference. Both the USRP and signal generator
>> are disciplined to the same reference. What I expected to see at the output
>> of the A2D (before any DC correction within the FPGA) is a DC signal with
>> noise on both I and Q. I expected that the atan of -Q/I (summed over some
>> interval to reduce noise) would provide the phase angle of the received CW,
>> which would be constant. Instead I received noise.
>>
>> According to the USRP2 schematic there are no capacitors in series
>> between the mixer and the A2D. And I'm viewing the samples before any DC
>> removal logic in the FPGA.
>>
>> Is there something obvious I'm missing? Are my assumptions correct?
>>
>
> Which daughterboard are you using?
>
> --n
>
>
>>
>> Thanks,
>> Brian
>>
>>
>> _______________________________________________
>> USRP-users mailing list
>> [email protected]
>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>>
>>
>
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Message: 5
Date: Thu, 05 Apr 2012 11:59:34 -0700
From: Philip Balister <[email protected]>
To: "Nowlan, Sean" <[email protected]>
Cc: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] E100 issue
Message-ID: <[email protected]>
Content-Type: text/plain; charset=ISO-8859-1
On 04/05/2012 09:53 AM, Nowlan, Sean wrote:
> I used the Ettus make script to build the latest master image (e1xx-003) on
> the 4GB SD card that came with the E100. After booting it up, I don't get any
> output from the console, and the Ethernet lights show no life when I plug in
> a good cable. Status lights "D" and "F" are lit, but none of the others light
> up during boot. Any thoughts?
Can you send the output of fdisk -l /dev/sd? when you put the card in
the PC?
Philip
>
> Thanks,
> Sean
>
>
>
>
> _______________________________________________
> USRP-users mailing list
> [email protected]
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
------------------------------
Message: 6
Date: Thu, 05 Apr 2012 12:00:30 -0700
From: Josh Blum <[email protected]>
To: [email protected]
Subject: Re: [USRP-users] Error on the page UHD_Linux
Message-ID: <[email protected]>
Content-Type: text/plain; charset=ISO-8859-1
On 04/04/2012 03:12 PM, Farhad Abdolian wrote:
> Hi Guys,
> I tried to install UHD on a new computer and found a problem on this page:
>
> http://code.ettus.com/redmine/ettus/projects/uhd/wiki/UHD_Linux
>
>
> sudo bash -c 'echo "deb
> http://files.ettus.com/binaries/stable/repo/uhd/ubuntu/`lsb_release -cs`
> `lsb_release -cs` main" > /etc/apt/sources.list.d/ettus.list'
> sudo apt-get update
> sudo apt-get install uhd
>
> The directory on ettus has change to :
> http://files.ettus.com/binaries/uhd_stable/repo/uhd/ubuntu/
>
Thanks, this is fixed. -josh
> Best regards,
> Farhad
>
>
>
>
>
>
>> ________________________________
>> From: Jason Abele <[email protected]>
>> To: Dan CaJacob <[email protected]>
>> Cc: "[email protected]" <[email protected]>
>> Sent: Wednesday, April 4, 2012 11:52 PM
>> Subject: Re: [USRP-users] USRP Calibration Routine
>>
>> On Wed, Apr 04, 2012 at 12:04:53PM -0400, Dan CaJacob wrote:
>>> Hi Josh,
>>>
>>> In some of the documentation for the three calibration utilities, you
>>> have indicated that the RF ports on the daughter-card being
>>> calibrated should be disconnected. I have always done that, but I
>>> was wondering if 50 Ohm terminations on the connectors would be of
>>> any benefit? Thanks.
>>
>> It won't hurt anything, but I doubt it will change much. The most
>> likely change would be in RX DC/LO which is not statically calibrated,
>> instead, it is handled by an average and subtract operation in the FPGA.
>>
>> During cal, the TX is switched away from the TX antenna into the
>> "closed" switch port, where it leaks into the RX which is listening to
>> the TX/RX antenna.
>>
>> So termination on RX2 should have no effect as that port is already
>> unused in calibration.
>>
>> However, the calibration code is open-source and there is no real reason
>> you can't experiment with other configurations or use the concepts
>> within it to fit the calibration routines to your application/system
>> design. It is important to note that transmitting close to full-power
>> directly into the receiver is likely to result in hardware damage, so
>> be careful of your settings and power-levels if you modify the
>> calibration routines.
>>
>> Jason
>>
>> _______________________________________________
>> USRP-users mailing list
>> [email protected]
>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>>
>>
>>
>>
>>
>> _______________________________________________
>> USRP-users mailing list
>> [email protected]
>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
------------------------------
Message: 7
Date: Thu, 5 Apr 2012 12:10:34 -0700
From: Ben Hilburn <[email protected]>
To: "Nowlan, Sean" <[email protected]>
Cc: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] E100 issue
Message-ID:
<CAOEVZkLiZDqnLtrsc=Tn7hGCH=zvxrcmshhhpz+5-bhbxwy...@mail.gmail.com>
Content-Type: text/plain; charset="windows-1252"
Also, if you still have the output of the Make script, will you share it?
Cheers,
Ben
----------------------------
Ben Hilburn <http://goo.gl/5DdZ3> @ Ettus Research, LLC<http://www.ettus.com/>
On Thu, Apr 5, 2012 at 9:53 AM, Nowlan, Sean <[email protected]>wrote:
> I used the Ettus make script to build the latest master image (e1xx-003)
> on the 4GB SD card that came with the E100. After booting it up, I don?t
> get any output from the console, and the Ethernet lights show no life when
> I plug in a good cable. Status lights ?D? and ?F? are lit, but none of the
> others light up during boot. Any thoughts?****
>
> ** **
>
> Thanks,****
>
> Sean****
>
> _______________________________________________
> USRP-users mailing list
> [email protected]
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
>
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Message: 8
Date: Thu, 5 Apr 2012 19:36:07 +0000
From: "Nowlan, Sean" <[email protected]>
To: Philip Balister <[email protected]>, "Ben Hilburn
([email protected])" <[email protected]>
Cc: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] E100 issue
Message-ID: <195933287DC65748BA7AE867BA8E430B62176FFE@apatlisdmbx02>
Content-Type: text/plain; charset="us-ascii"
I've attached output from both the make script and fdisk -l. Thanks!
>Also, if you still have the output of the Make script, will you share it?
>
>Cheers,
>Ben
-----Original Message-----
From: Philip Balister [mailto:[email protected]]
Sent: Thursday, April 05, 2012 3:00 PM
To: Nowlan, Sean
Cc: [email protected]
Subject: Re: [USRP-users] E100 issue
On 04/05/2012 09:53 AM, Nowlan, Sean wrote:
> I used the Ettus make script to build the latest master image (e1xx-003) on
> the 4GB SD card that came with the E100. After booting it up, I don't get any
> output from the console, and the Ethernet lights show no life when I plug in
> a good cable. Status lights "D" and "F" are lit, but none of the others light
> up during boot. Any thoughts?
Can you send the output of fdisk -l /dev/sd? when you put the card in the PC?
Philip
>
> Thanks,
> Sean
>
>
>
>
> _______________________________________________
> USRP-users mailing list
> [email protected]
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
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Message: 9
Date: Thu, 5 Apr 2012 12:54:39 -0700
From: Ben Hilburn <[email protected]>
To: "Nowlan, Sean" <[email protected]>
Cc: Philip Balister <[email protected]>,
"[email protected]" <[email protected]>
Subject: Re: [USRP-users] E100 issue
Message-ID:
<caoevzkj8gfjm7tykxfkeewtgplzggbqbt+wd4urqap6ax19...@mail.gmail.com>
Content-Type: text/plain; charset="iso-8859-1"
Responding off-list so we don't hammer the list with attachments...
Cheers,
Ben
----------------------------
Ben Hilburn <http://goo.gl/5DdZ3> @ Ettus Research, LLC<http://www.ettus.com/>
On Thu, Apr 5, 2012 at 12:36 PM, Nowlan, Sean
<[email protected]>wrote:
> I've attached output from both the make script and fdisk -l. Thanks!
>
>
> >Also, if you still have the output of the Make script, will you share it?
> >
> >Cheers,
> >Ben
>
>
> -----Original Message-----
> From: Philip Balister [mailto:[email protected]]
> Sent: Thursday, April 05, 2012 3:00 PM
> To: Nowlan, Sean
> Cc: [email protected]
> Subject: Re: [USRP-users] E100 issue
>
> On 04/05/2012 09:53 AM, Nowlan, Sean wrote:
> > I used the Ettus make script to build the latest master image (e1xx-003)
> on the 4GB SD card that came with the E100. After booting it up, I don't
> get any output from the console, and the Ethernet lights show no life when
> I plug in a good cable. Status lights "D" and "F" are lit, but none of the
> others light up during boot. Any thoughts?
>
> Can you send the output of fdisk -l /dev/sd? when you put the card in the
> PC?
>
> Philip
>
> >
> > Thanks,
> > Sean
> >
> >
> >
> >
> > _______________________________________________
> > USRP-users mailing list
> > [email protected]
> > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
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Message: 10
Date: Thu, 5 Apr 2012 13:17:33 -0700 (PDT)
From: Farhad Abdolian <[email protected]>
To: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] FPGA and FW update of N210
Message-ID:
<[email protected]>
Content-Type: text/plain; charset="iso-8859-1"
HI John,
I did and the results are the same:
linux; GNU C++ version 4.4.3; Boost_104000; UHD_003.004.000-32-g51c81a39
Error: LookupError: KeyError: No devices found for ----->
Empty Device Address
And uhd_find_devices gives
linux; GNU C++ version 4.4.3; Boost_104000; UHD_003.004.000-32-g51c81a39
No UHD Devices Found
I am getting frustrated, the ping works without any problems:
ping 192.168.10.2
PING 192.168.10.2 (192.168.10.2) 56(84) bytes of data.
64 bytes from 192.168.10.2: icmp_seq=1 ttl=64 time=0.069 ms
64 bytes from 192.168.10.2: icmp_seq=2 ttl=64 time=0.060 ms
64 bytes from 192.168.10.2: icmp_seq=3 ttl=64 time=0.058 ms
64 bytes from 192.168.10.2: icmp_seq=4 ttl=64 time=0.062 ms
^C
--- 192.168.10.2 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3000ms
rtt min/avg/max/mdev = 0.058/0.062/0.069/0.007 ms
I have to figure out what the problem is!
BR,
Farhad
>________________________________
> From: Jonathan Fox <[email protected]>
>To: Farhad Abdolian <[email protected]>
>Cc: "[email protected]" <[email protected]>
>Sent: Thursday, April 5, 2012 3:42 PM
>Subject: Re: [USRP-users] FPGA and FW update of N210
>
>Farhad,
>
>Please try "uhd_usrp_probe".
>
>-Jon
>
>On 4/5/12, Farhad Abdolian <[email protected]> wrote:
>> Hi,
>> How
>>? do I know what revision my USRP N210 is? I am trying to update the FPGA
>>? image on the 2 USRPs I have and don't know which FPGA code to use.
>>
>> The problem I have is that I can not detect the USRPs using
>> uhd_find_devices.
>>
>> I can ping the USRP and I can upgrade the FW but I can not 'detect' it and
>> use it.
>>
>> Really appreciate your help,
>>
>> BR,
>> Farhad
>
>
>
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Message: 11
Date: Thu, 05 Apr 2012 13:34:45 -0700
From: Josh Blum <[email protected]>
To: [email protected]
Subject: Re: [USRP-users] FPGA and FW update of N210
Message-ID: <[email protected]>
Content-Type: text/plain; charset=ISO-8859-1
On 04/05/2012 01:17 PM, Farhad Abdolian wrote:
> HI John,
> I did and the results are the same:
>
>
> linux; GNU C++ version 4.4.3; Boost_104000; UHD_003.004.000-32-g51c81a39
>
> Error: LookupError: KeyError: No devices found for ----->
> Empty Device Address
>
>
> And uhd_find_devices gives
>
> linux; GNU C++ version 4.4.3; Boost_104000; UHD_003.004.000-32-g51c81a39
> No UHD Devices Found
>
> I am getting frustrated, the ping works without any problems:
> ping 192.168.10.2
> PING 192.168.10.2 (192.168.10.2) 56(84) bytes of data.
> 64 bytes from 192.168.10.2: icmp_seq=1 ttl=64 time=0.069 ms
> 64 bytes from 192.168.10.2: icmp_seq=2 ttl=64 time=0.060 ms
> 64 bytes from 192.168.10.2: icmp_seq=3 ttl=64 time=0.058 ms
> 64 bytes from 192.168.10.2: icmp_seq=4 ttl=64 time=0.062 ms
> ^C
> --- 192.168.10.2 ping statistics ---
> 4 packets transmitted, 4 received, 0% packet loss, time 3000ms
> rtt min/avg/max/mdev = 0.058/0.062/0.069/0.007 ms
>
>
> I have to figure out what the problem is!
This could be a firewall issue:
does uhd_find_devices --args="addr=192.168.10.2" work?
see http://files.ettus.com/uhd_docs/manual/html/usrp2.html#firewall-issues
-josh
------------------------------
Message: 12
Date: Thu, 5 Apr 2012 23:45:52 +0300
From: Orkhan Badirkhanli <[email protected]>
To: Farhad Abdolian <[email protected]>
Cc: "[email protected]" <[email protected]>
Subject: Re: [USRP-users] FPGA and FW update of N210
Message-ID:
<cadl6qmgnd5vsw0prql2pz9vxz4tztaa92sp71oi08l4xovt...@mail.gmail.com>
Content-Type: text/plain; charset="iso-8859-1"
Farhad
I had very similar problem when I first connected the usrp. I was getting
ping responses but uhd_find_devices and other similar functions did not
work. I simply burned fw and fpga images again and the problem resolved.
Did you have any luck with burning fpga and fw images?
On Thu, Apr 5, 2012 at 11:17 PM, Farhad Abdolian <[email protected]>wrote:
> HI John,
> I did and the results are the same:
>
> linux; GNU C++ version 4.4.3; Boost_104000; UHD_003.004.000-32-g51c81a39
>
> Error: LookupError: KeyError: No devices found for ----->
> Empty Device Address
>
> And uhd_find_devices gives
>
> linux; GNU C++ version 4.4.3; Boost_104000; UHD_003.004.000-32-g51c81a39
> No UHD Devices Found
>
> I am getting frustrated, the ping works without any problems:
> ping 192.168.10.2
> PING 192.168.10.2 (192.168.10.2) 56(84) bytes of data.
> 64 bytes from 192.168.10.2: icmp_seq=1 ttl=64 time=0.069 ms
> 64 bytes from 192.168.10.2: icmp_seq=2 ttl=64 time=0.060 ms
> 64 bytes from 192.168.10.2: icmp_seq=3 ttl=64 time=0.058 ms
> 64 bytes from 192.168.10.2: icmp_seq=4 ttl=64 time=0.062 ms
> ^C
> --- 192.168.10.2 ping statistics ---
> 4 packets transmitted, 4 received, 0% packet loss, time 3000ms
> rtt min/avg/max/mdev = 0.058/0.062/0.069/0.007 ms
>
> I have to figure out what the problem is!
> BR,
> Farhad
>
> ------------------------------
> *From:* Jonathan Fox <[email protected]>
> *To:* Farhad Abdolian <[email protected]>
> *Cc:* "[email protected]" <[email protected]>
> *Sent:* Thursday, April 5, 2012 3:42 PM
>
> *Subject:* Re: [USRP-users] FPGA and FW update of N210
>
> Farhad,
>
> Please try "uhd_usrp_probe".
>
> -Jon
>
> On 4/5/12, Farhad Abdolian <[email protected]> wrote:
> > Hi,
> > How
> > do I know what revision my USRP N210 is? I am trying to update the FPGA
> > image on the 2 USRPs I have and don't know which FPGA code to use.
> >
> > The problem I have is that I can not detect the USRPs using
> > uhd_find_devices.
> >
> > I can ping the USRP and I can upgrade the FW but I can not 'detect' it
> and
> > use it.
> >
> > Really appreciate your help,
> >
> > BR,
> > Farhad
>
>
>
> _______________________________________________
> USRP-users mailing list
> [email protected]
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
>
--
Orkhan
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Message: 13
Date: Thu, 5 Apr 2012 21:20:38 +0000
From: "Knee, Peter A" <[email protected]>
To: "[email protected]" <[email protected]>
Subject: [USRP-users] Dropped data
Message-ID:
<[email protected]>
Content-Type: text/plain; charset="us-ascii"
Hey all!
I'm currently using an N210 to try and capture and store I/Q data whenever a
signal is present. As this is part of a larger package, we've implemented all
this in C++ using multiple threads as it's expected that there will be lots of
downstream processing on the data in the future. Currently I use a single
thread to load the data from the USRP and then store that data in a shared
memory location that can be processed by the other threads. I believe that the
overhead in maintaining continuity between the threads so that data is not
over-written or read out of sequence is causing issues with the capture of the
data. Specifically, it appears as though I am dropping samples after each
packet is read and loaded into shared memory.
I've attached a plot of what we're seeing. This is the unwrapped phase data
after being written out to a file. We generated and transmitted a CW tone
slightly offset from the center frequency of the receiver. The unwrapped phase
is linear as expected for a CW tone. However, after exactly the number of
samples streamed from the device, we see a phase jump, seemingly indicating
that we are dropping samples after each read. The device is setup in
continuous streaming mode.
Does anyone have any idea why we might be dropping samples? There are no error
codes present in the received metadata so I don't believe that the thread
overhead is causing buffer overruns.
Any help you can provide would be appreciated.
Thanks,
Peter Knee
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------------------------------
Message: 14
Date: Thu, 05 Apr 2012 17:35:28 -0700
From: Josh Blum <[email protected]>
To: [email protected]
Subject: Re: [USRP-users] Dropped data
Message-ID: <[email protected]>
Content-Type: text/plain; charset=ISO-8859-1
> Does anyone have any idea why we might be dropping samples? There
> are no error codes present in the received metadata so I don't
> believe that the thread overhead is causing buffer overruns.
>
Not sure why. It might be worth checking the timestamps and packet
lengths. The next packet time should be the last packet time + last
packet length/sample rate.
The jumps look pretty regular, several a second. It might be good to
dump a seconds worth of samples to file (right out of the interface) and
catch the discontinuity in the act.
-josh
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