[USRP-users] PPS sync with USRP E310 timeout error

[Cho, Daniel J (332C) via USRP-users]

Hello -

I am using 2 USRP E310 which I would like to frequency sync together.  I am 
using a frequency generator which is generating a 1 PPS (1Hz sine wave) signal 
which I put through a power splitter to provide both USRPs with the same 1 PPS 
signal.  I configured the rx_samples_to_file and tx_samples_from_file codes to 
allow me to use the external 1PPS signal by including the following into the 
code:


//sleep off if gpsdo detected and time next pps already set


boost::this_thread::sleep(boost::posix_time::seconds(1));



//set time source if specified


if (not time_source.empty()) usrp->set_time_source(time_source);



//set the time at an unknown pps (will throw if no pps)


std::cout << std::endl << "Attempt to detect the PPS and set the time..." << 
std::endl << std::endl;


usrp->set_time_unknown_pps(uhd::time_spec_t(0.0));


std::cout << std::endl << "Success!" << std::endl << std::endl;


When I run the rx_samples_to_file code with the above code included, I get a 
timeout error.  I found that it was due to the line 
"usrp->set_time_unknown_pps(uhd::time_spec_t(0.0));"
How can I get my two USRPs frequency synced without getting this error?

Also, I saw that the 1 PPS signal provided to the USRP should be 3.3V - 5V.  
When I put a 1 PPS signal that strong on the spectrum analyzer, it shows a 
power output above +10 dBm.  I know that the max RX input power is -15 dBm so I 
was hesitant to input a 1 PPS signal that strong.  The 1 PPS signal I put into 
the sync port was 100 mV.  Even with a 1 PPS signal with an output power of 
100mV, I am still able to run the test_pps_input program successfully.

So in summary, should I just send a 1 PPS signal with a power output above +10 
dBm which equates to the 3.3V - 5V to the sync port even though I am able to 
run the test_pps_input program successfully with 100mV?  How can I get the 
rx_samples_to_file program to run successfully without giving me a timeout 
error using the above lines of code?

Thanks
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Re: [USRP-users] Trying to verify Rx MIMO operation of x310

[Rob Kossler via USRP-users]

Mark,
There is an Ettus UHD-only utility called kitchen_sink that can do multiple
channels to file (either one file interleaved or multiple individual files,
I believe).  This is not in the examples folder but in
"uhd/tools/kitchen_sink".  This does not automatically compile with the
overall build of uhd and examples, but you can create a build folder and
compile this individually.  The command line options are numerous so it is
a bit complex, but it can do the job of recording multiple of channels of
incoming data to file.

Rob


On Tue, Aug 1, 2017 at 11:10 AM, Derek Kozel via USRP-users <
usrp-users@lists.ettus.com> wrote:

> Hi Mark,
>
> Unfortunately you're up against the limits of the included examples. There
> are no UHD only examples which store multiple channels of samples to a
> file. The rx_multi_samples shows the steps involved in setting up the
> channels, but doesn't implement the functionality shown in
> rx_samples_to_file to write to a file.
>
> Yes, uhd_fft can be used to view multiple channels. GNU Radio's framework
> makes it easy to implement the more advanced application layer features.
> The arguments will be almost the same as for rx_multi_samples to file.
> Check out the help message for uhd_fft to see all the options. Simply
> supplying the frequency of interest and the same --channels 0,1 should show
> you plots of both channel's spectrum and time series data.
>
> To save data from both channels you will need to construct a flowgraph in
> GNU Radio. There are some examples supplied with gr-uhd which demonstrate
> the basics of connecting and configuring the USRP source. If you have
> trouble let us know here or on the GNU Radio mailing list.
>
> Regards,
> Derek
>
> On Tue, Aug 1, 2017 at 3:14 PM, Mark Koenig  iubelttechnologies.com> wrote:
>
>> Thanks Derek.
>>
>>
>>
>> I was setting up rx_multi_samples the following way:
>>
>>
>>
>> ./rx_samples –args=”addr=192.168.40.2” –nsamps=1000 –rate=100e6
>> –sync=now –subdev=”A:0 B:0” –channels=”0,1”
>>
>>
>>
>> I see a lot of verbose output, like:
>>
>>
>>
>> Received Packet:  1996 samples, 1 full secs, 0.50 frac secs
>>
>>
>>
>> But, I don’t get any file outputs or anything else.  The collection ends
>> and I am left wondering what just happened.  Can I use uhd_fft to look at
>> the MIMO stream?
>>
>>
>>
>> Also, there is no place to enter a frequency to collect, should there be?
>>
>>
>>
>> Mark
>>
>>
>>
>> *From: *Derek Kozel 
>> *Date: *Tuesday, August 1, 2017 at 10:08 AM
>> *To: *Mark Koenig 
>> *Cc: *"usrp-users@lists.ettus.com" 
>> *Subject: *Re: [USRP-users] Trying to verify Rx MIMO operation of x310
>>
>>
>>
>> Hello Mark,
>>
>> rx_samples_to_file will only receive a single channel. It is a minimal
>> example.
>>
>> Try:
>>
>> rx_multi_samples --channels 0,1
>>
>> This will receive two channels, a pair of UBXs only has one RX channel
>> per daughterboard so UHD can infer the sub device specification. The
>> default sample rate is 100 MS/s so both channels will fit into a single 10
>> GigE connection. Make sure to follow the advice of any warnings printed to
>> improve the throughput of your network interface card.
>>
>> If you have an external 1PPS source you can add `--sync pps --secs 0.1`
>> to the above parameters to synchronize the two channels. The example
>> currently forces an external source when synchronizing. If you
>> remove/comment out line 98 and recompile it will use the internal source.
>>
>> Regards,
>>
>> Derek
>>
>>
>>
>>
>>
>>
>> On Tue, Aug 1, 2017 at 2:46 PM, Mark Koenig via USRP-users <
>> usrp-users@lists.ettus.com> wrote:
>>
>> I currently have an x310 with a ubx-40 in each of slots A and B.  I have
>> one 10Gig Ethernet connection hooked up, and would like to receive on both
>> channels A and B.
>>
>>
>>
>> I tried using the “rx_multi_samples” function, but I didn’t get a good
>> feeling I was collecting on both channels.  I tried using the
>> “rx_samples_to_file” function, but didn’t see a coherent collection on A
>> and B, when setting the subdev to “A:0 B:0”.
>>
>> Finally, I tried the “uhd_fft”, and saw collection in channel A, but
>> nothing from channel B, while setting subdev=”A:0 B:0”.
>>
>>
>>
>> Am I doing something incorrectly, or is there another function I should
>> try?
>>
>>
>>
>> Thanks
>>
>>
>>
>> Mark
>>
>>
>>
>>
>> ___
>> USRP-users mailing list
>> USRP-users@lists.ettus.com
>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>>
>>
>>
>
>
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[USRP-users] How Do I get a py File Transferred Over to The E310

[Matheou, Konstantin J. (GRC-LCI0)[ZIN TECHNOLOGIES INC] via USRP-users]

To All,

I realize this is a rookie question, but I looked all over on the net to find 
the answer.

First off, I realize that thGNU radio and UHD.

So, I realize I need to create a pythin file offline via GNU radio Companion on 
my laptop.  And of course, do not include any graphical functions.

I asl was able to connect to the E310 via the USB 2.0 through a Linux 
terminal...  and when I do a pwd, I am at home/root.

I realized cp and mv is the Linux way to copy and paste method for Linux.

My question is what is the process to move my python file from the laptop Linux 
directory to the E310 hardware via the USB 2.0 connection?

Likewise, once I move it to a directory on the E310 hardware, do I just type 
python grcFile.py to run the file on E310 hardware?

Thanks,

Konstantin
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[USRP-users] USB connector on B205mini-i

[Nirmala Soundararajan via USRP-users]

Hi,

Has anyone tried to use Matlab with B205mini-i on windows? Apparently
Matlab does'nt recognise the board when plugged to USB 3.0 port. It however
works when used with USB 2.0 ports. Ettus recommends to use USB 3.0
specially on B205mini i.

Request for help

regards

Nirmala
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Re: [USRP-users] Error message while running init_usrp

[Nauman Iqbal via USRP-users]

Yes this is an X310 configured in a megausrp for massive mimo. Same device 
works fine on Ubuntu but always makes this issue on Fedora, UHD is installed 
correctly, no specific issues in installation.

Regards

Nauman

From: USRP-users [mailto:usrp-users-boun...@lists.ettus.com] On Behalf Of 
Marcus Müller via USRP-users
Sent: 01 August 2017 17:20
To: usrp-users@lists.ettus.com
Subject: Re: [USRP-users] Error message while running init_usrp


Hi Nauman,

that's not supposed to happen. So, I guess this is an X3x0, right?

Best regards,

Marcus

On 08/01/2017 06:09 PM, Nauman Iqbal via USRP-users wrote:
Hi,
 I am getting following error while I run compile and run init_usrp on 
a machine running fedora. I have usrp with a modified ip but when I run same 
from a Ubuntu based machine it works fine.


Error: LookupError: Path not found in tree: /mboards/0/xbar/Radio_0/ports/in


Any clues?

Regards

Nauman




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Re: [USRP-users] One USRP device is not connected to the host computer

[Derek Kozel via USRP-users]

Hi Adhitha,

I'm glad that's worked for you.

Best regards,
Derek

On Tue, Aug 1, 2017 at 4:19 PM, Adhitha Dias 
wrote:

> Hi Derek,
>
> I tried with the large netmask. Now it's working. Thank you so much for
> the help. Really appreciate it!
>
> I am using UHD version 3.10.1.0 in Ubuntu 16.04.2 OS.
>
> Regards,
> Adhitha
>
> On 1 Aug 2017 11:09 p.m., "Derek Kozel"  wrote:
>
>> Hello Adhitha,
>>
>> If you are connecting only one USRP at a time directly to the computer
>> and see one work and one not then my first guess would be that the IP
>> address has changed on the second one. Try running uhd_find_devices, this
>> will work if the IP address is different but still on the same subnet. If
>> you do not see it with this then try increasing your netmask to something
>> like 255.255.0.0 to catch a broader range of possible addresses.
>>
>> More networking info can be found in the manual.
>> http://files.ettus.com/manual/page_usrp_x3x0.html#x3x0_setup_network
>>
>> What version of UHD are you using and what operating system?
>>
>> Regards,
>> Derek
>>
>> On Tue, Aug 1, 2017 at 9:49 AM, Adhitha Dias via USRP-users <
>> usrp-users@lists.ettus.com> wrote:
>>
>>> Hi,
>>>
>>> I am a new user of USRP and UHD software. I have 2 X310 USRPs but the
>>> connection is established with only one USRP (first USRP). When I ping the
>>> other USRP (say second USRP) it gives ICMP destination host unreachable
>>> message. I am uncertain on how to debug or if there is something wrong with
>>> its hardware configuration.
>>>
>>> I connected one USRP at a time using the same Ethernet cable with the
>>> same host computer when checking. Any help would be highly appreciated!
>>>
>>> Thank you.
>>>
>>> Best regards,
>>> Adhitha Dias
>>> Undergraduate,
>>> Department of Electronics and Telecommunication,
>>> University of Moratuwa,
>>> Sri Lanka.
>>>
>>> ___
>>> USRP-users mailing list
>>> USRP-users@lists.ettus.com
>>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>>>
>>>
>>
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Re: [USRP-users] Trying to verify Rx MIMO operation of x310

[Derek Kozel via USRP-users]

Hi Mark,

Unfortunately you're up against the limits of the included examples. There
are no UHD only examples which store multiple channels of samples to a
file. The rx_multi_samples shows the steps involved in setting up the
channels, but doesn't implement the functionality shown in
rx_samples_to_file to write to a file.

Yes, uhd_fft can be used to view multiple channels. GNU Radio's framework
makes it easy to implement the more advanced application layer features.
The arguments will be almost the same as for rx_multi_samples to file.
Check out the help message for uhd_fft to see all the options. Simply
supplying the frequency of interest and the same --channels 0,1 should show
you plots of both channel's spectrum and time series data.

To save data from both channels you will need to construct a flowgraph in
GNU Radio. There are some examples supplied with gr-uhd which demonstrate
the basics of connecting and configuring the USRP source. If you have
trouble let us know here or on the GNU Radio mailing list.

Regards,
Derek

On Tue, Aug 1, 2017 at 3:14 PM, Mark Koenig <
mark.koe...@iubelttechnologies.com> wrote:

> Thanks Derek.
>
>
>
> I was setting up rx_multi_samples the following way:
>
>
>
> ./rx_samples –args=”addr=192.168.40.2” –nsamps=1000 –rate=100e6
> –sync=now –subdev=”A:0 B:0” –channels=”0,1”
>
>
>
> I see a lot of verbose output, like:
>
>
>
> Received Packet:  1996 samples, 1 full secs, 0.50 frac secs
>
>
>
> But, I don’t get any file outputs or anything else.  The collection ends
> and I am left wondering what just happened.  Can I use uhd_fft to look at
> the MIMO stream?
>
>
>
> Also, there is no place to enter a frequency to collect, should there be?
>
>
>
> Mark
>
>
>
> *From: *Derek Kozel 
> *Date: *Tuesday, August 1, 2017 at 10:08 AM
> *To: *Mark Koenig 
> *Cc: *"usrp-users@lists.ettus.com" 
> *Subject: *Re: [USRP-users] Trying to verify Rx MIMO operation of x310
>
>
>
> Hello Mark,
>
> rx_samples_to_file will only receive a single channel. It is a minimal
> example.
>
> Try:
>
> rx_multi_samples --channels 0,1
>
> This will receive two channels, a pair of UBXs only has one RX channel per
> daughterboard so UHD can infer the sub device specification. The default
> sample rate is 100 MS/s so both channels will fit into a single 10 GigE
> connection. Make sure to follow the advice of any warnings printed to
> improve the throughput of your network interface card.
>
> If you have an external 1PPS source you can add `--sync pps --secs 0.1` to
> the above parameters to synchronize the two channels. The example currently
> forces an external source when synchronizing. If you remove/comment out
> line 98 and recompile it will use the internal source.
>
> Regards,
>
> Derek
>
>
>
>
>
>
> On Tue, Aug 1, 2017 at 2:46 PM, Mark Koenig via USRP-users <
> usrp-users@lists.ettus.com> wrote:
>
> I currently have an x310 with a ubx-40 in each of slots A and B.  I have
> one 10Gig Ethernet connection hooked up, and would like to receive on both
> channels A and B.
>
>
>
> I tried using the “rx_multi_samples” function, but I didn’t get a good
> feeling I was collecting on both channels.  I tried using the
> “rx_samples_to_file” function, but didn’t see a coherent collection on A
> and B, when setting the subdev to “A:0 B:0”.
>
> Finally, I tried the “uhd_fft”, and saw collection in channel A, but
> nothing from channel B, while setting subdev=”A:0 B:0”.
>
>
>
> Am I doing something incorrectly, or is there another function I should
> try?
>
>
>
> Thanks
>
>
>
> Mark
>
>
>
>
> ___
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> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
>
>
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Re: [USRP-users] One USRP device is not connected to the host computer

[Derek Kozel via USRP-users]

Hello Adhitha,

If you are connecting only one USRP at a time directly to the computer and
see one work and one not then my first guess would be that the IP address
has changed on the second one. Try running uhd_find_devices, this will work
if the IP address is different but still on the same subnet. If you do not
see it with this then try increasing your netmask to something like
255.255.0.0 to catch a broader range of possible addresses.

More networking info can be found in the manual.
http://files.ettus.com/manual/page_usrp_x3x0.html#x3x0_setup_network

What version of UHD are you using and what operating system?

Regards,
Derek

On Tue, Aug 1, 2017 at 9:49 AM, Adhitha Dias via USRP-users <
usrp-users@lists.ettus.com> wrote:

> Hi,
>
> I am a new user of USRP and UHD software. I have 2 X310 USRPs but the
> connection is established with only one USRP (first USRP). When I ping the
> other USRP (say second USRP) it gives ICMP destination host unreachable
> message. I am uncertain on how to debug or if there is something wrong with
> its hardware configuration.
>
> I connected one USRP at a time using the same Ethernet cable with the same
> host computer when checking. Any help would be highly appreciated!
>
> Thank you.
>
> Best regards,
> Adhitha Dias
> Undergraduate,
> Department of Electronics and Telecommunication,
> University of Moratuwa,
> Sri Lanka.
>
> ___
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>
>
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[USRP-users] One USRP device is not connected to the host computer

[Adhitha Dias via USRP-users]

Hi,

I am a new user of USRP and UHD software. I have 2 X310 USRPs but the
connection is established with only one USRP (first USRP). When I ping the
other USRP (say second USRP) it gives ICMP destination host unreachable
message. I am uncertain on how to debug or if there is something wrong with
its hardware configuration.

I connected one USRP at a time using the same Ethernet cable with the same
host computer when checking. Any help would be highly appreciated!

Thank you.

Best regards,
Adhitha Dias
Undergraduate,
Department of Electronics and Telecommunication,
University of Moratuwa,
Sri Lanka.
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[USRP-users] N210 DSP Processing Chain

[Dave NotTelling via USRP-users]

What happens to samples between the ADC and receiving them from UHD?  Also,
is there any way to get the raw IQ off of the ADC itself?  I feel like
there isn't only because the ADC (to the best of my knowledge) runs at 100
MSPS which is too high a rate to send over the 1 Gb/s link.

Thanks!
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Re: [USRP-users] Trying to verify Rx MIMO operation of x310

[Mark Koenig via USRP-users]

Thanks Derek.

I was setting up rx_multi_samples the following way:

./rx_samples –args=”addr=192.168.40.2” –nsamps=1000 –rate=100e6 –sync=now 
–subdev=”A:0 B:0” –channels=”0,1”

I see a lot of verbose output, like:

Received Packet:  1996 samples, 1 full secs, 0.50 frac secs

But, I don’t get any file outputs or anything else.  The collection ends and I 
am left wondering what just happened.  Can I use uhd_fft to look at the MIMO 
stream?

Also, there is no place to enter a frequency to collect, should there be?

Mark

From: Derek Kozel 
Date: Tuesday, August 1, 2017 at 10:08 AM
To: Mark Koenig 
Cc: "usrp-users@lists.ettus.com" 
Subject: Re: [USRP-users] Trying to verify Rx MIMO operation of x310

Hello Mark,
rx_samples_to_file will only receive a single channel. It is a minimal example.
Try:
rx_multi_samples --channels 0,1
This will receive two channels, a pair of UBXs only has one RX channel per 
daughterboard so UHD can infer the sub device specification. The default sample 
rate is 100 MS/s so both channels will fit into a single 10 GigE connection. 
Make sure to follow the advice of any warnings printed to improve the 
throughput of your network interface card.
If you have an external 1PPS source you can add `--sync pps --secs 0.1` to the 
above parameters to synchronize the two channels. The example currently forces 
an external source when synchronizing. If you remove/comment out line 98 and 
recompile it will use the internal source.
Regards,
Derek




On Tue, Aug 1, 2017 at 2:46 PM, Mark Koenig via USRP-users 
> wrote:
I currently have an x310 with a ubx-40 in each of slots A and B.  I have one 
10Gig Ethernet connection hooked up, and would like to receive on both channels 
A and B.

I tried using the “rx_multi_samples” function, but I didn’t get a good feeling 
I was collecting on both channels.  I tried using the “rx_samples_to_file” 
function, but didn’t see a coherent collection on A and B, when setting the 
subdev to “A:0 B:0”.
Finally, I tried the “uhd_fft”, and saw collection in channel A, but nothing 
from channel B, while setting subdev=”A:0 B:0”.

Am I doing something incorrectly, or is there another function I should try?

Thanks

Mark


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Re: [USRP-users] Trying to verify Rx MIMO operation of x310

[Derek Kozel via USRP-users]

Hello Mark,

rx_samples_to_file will only receive a single channel. It is a minimal
example.

Try:
rx_multi_samples --channels 0,1

This will receive two channels, a pair of UBXs only has one RX channel per
daughterboard so UHD can infer the sub device specification. The default
sample rate is 100 MS/s so both channels will fit into a single 10 GigE
connection. Make sure to follow the advice of any warnings printed to
improve the throughput of your network interface card.

If you have an external 1PPS source you can add `--sync pps --secs 0.1` to
the above parameters to synchronize the two channels. The example currently
forces an external source when synchronizing. If you remove/comment out
line 98 and recompile it will use the internal source.

Regards,
Derek





On Tue, Aug 1, 2017 at 2:46 PM, Mark Koenig via USRP-users <
usrp-users@lists.ettus.com> wrote:

> I currently have an x310 with a ubx-40 in each of slots A and B.  I have
> one 10Gig Ethernet connection hooked up, and would like to receive on both
> channels A and B.
>
>
>
> I tried using the “rx_multi_samples” function, but I didn’t get a good
> feeling I was collecting on both channels.  I tried using the
> “rx_samples_to_file” function, but didn’t see a coherent collection on A
> and B, when setting the subdev to “A:0 B:0”.
>
> Finally, I tried the “uhd_fft”, and saw collection in channel A, but
> nothing from channel B, while setting subdev=”A:0 B:0”.
>
>
>
> Am I doing something incorrectly, or is there another function I should
> try?
>
>
>
> Thanks
>
>
>
> Mark
>
>
>
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[USRP-users] Trying to verify Rx MIMO operation of x310

[Mark Koenig via USRP-users]

I currently have an x310 with a ubx-40 in each of slots A and B.  I have one 
10Gig Ethernet connection hooked up, and would like to receive on both channels 
A and B.

I tried using the “rx_multi_samples” function, but I didn’t get a good feeling 
I was collecting on both channels.  I tried using the “rx_samples_to_file” 
function, but didn’t see a coherent collection on A and B, when setting the 
subdev to “A:0 B:0”.
Finally, I tried the “uhd_fft”, and saw collection in channel A, but nothing 
from channel B, while setting subdev=”A:0 B:0”.

Am I doing something incorrectly, or is there another function I should try?

Thanks

Mark

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