[USRP-users] Independent use of ethernet ports on Ettus x310?

Derek Kozel derek.kozel at ettus.com
Fri Nov 17 13:54:12 EST 2017


Hello Chad,

You'll need a program which can receive from both channels at once. The
claiming means that two processes cannot access the same USRP at the same
time. The rx_multi_samples shows receiving two sample streams on the same
frequency and the same rate. You'll likely need to write your own program
which implements the behavior you want. It is absolutely possible to start
and stop the two receive channels when you want, separately from each
other. No example shows this, but it is very easy and particularly in GNU
Radio it is easy to put together in just a few minutes once you're used to
the environment.

It is possible for the X300/X310 to have both SFP+ ports as 1 gigabit
Ethernet, but this hasn't been requested often and pre-built images aren't
available. Most of the time moving to 10 Gigabit Ethernet is an easier and
better option. Far higher sample rates, and thus bandwidths, are possible.
Thank you for pointing out those two places where it is described. We will
talk internally about how best to describe that functionality.

The USRP Sink block can be used to transmit, I see you already have a
working flowgraph and an understanding of the subdevice specifications.

Since you're using GNU Radio, all you need to do is put down one USRP
source and use the subdevice specification to select the A or B side of the
X310, to choose the SBX to receive from. Selecting when to save the samples
to disk can be as simple as a push button, a small amount of python, and a
file sink. There was an example of this on this or the GNU Radio list last
year, I'll try and find it but the logic was pretty simple. The copy block
can be used to selectively throw away or pass through samples. This is
followed by the file sink and have the filename be created dynamically by
putting an python expression in the filename field. You may be best served
by moving to a direct Python program rather than just GNU Radio Companion
since it will give you more control and flexibility.


On Fri, Nov 17, 2017 at 5:28 PM, Chad Spooner via USRP-users <
usrp-users at lists.ettus.com> wrote:

> Neel:
>
> But what does Ettus mean by "Dual 1 Gigabit Ethernet" on those links? (Not
> "Dual 10 Gigabit Ethernet".)
> See attached screen shots from the Ettus.com links I sent previously.
>
> I am currently using the UHD Source block with the SBX and a UHD Sink
> block with the WBX in the
> working flowgraph. What I want to do is occasionally obtain complex
> samples from the SBX and process
> them outside of GRC. I can think of two ways to get data from the SBX to a
> file. The first is through
> uhd_rx_cfile and the second is through the use of a File Sink in the
> flowgraph. But while the flowgraph
> is running, I can't successfully call uhd_rx_cfile. If I use the File
> Sink, I'll have to be able to grab samples
> at irregular intervals outside of GRC, and I'm not sure if that will cause
> a problem for the function
> that is continuously writing to the file. I'll try.
>
> Plan B could be to just use a second USRP.
>
> Thanks,
>
> C
>
> On Fri, 2017-11-17 at 09:00 -0800, Neel Pandeya wrote:
>
> Hello Chad:
>
> By "dual 10 Gigabit Ethernet", we mean that both Port 0 and Port 1 are
> being used with 10 Gigabit Ethernet links simultaneously. Both links must
> connect to the same host computer; you cannot have one link connected to
> system A, and the other link connected to system B.
>
> In GNU Radio, you can receive from your SBX by using a USRP UHD Source
> block, and you can transmit with your WBX by using a USRP UHD Sink block.
>
> --Neel Pandeya
>
>
>
> On 17 November 2017 at 08:33, Chad Spooner <cmspooner at nwra.com> wrote:
>
> Neel:
>
> Thanks very much for the helpful reply.
>
> MY x310 has both a SBX and a WBX installed. The working configuration I
> mentioned
> has the WBX transmitting and the SBX receiving simultaneously. But how do
> I get
> data chunks from the SBX while the flowgraph that implements this
> simultaneous
> operation is running? I suppose I can use a File Sink, but I'm not sure
> how to read
> segments of the growing file while it is constantly being written to by
> the SDR/host.
>
> I think something that confuses me about the Ettus online documentation is
> the
> use of the phrases "Dual 1 Gigabit Ethernet" and "Dual 10 Gigabit
> Ethernet." These
> both appear, for example, on the following links:
>
> https://www.ettus.com/product/details/X310-KIT
> https://kb.ettus.com/X300/X310
>
> I thought I understood the "Dual 10 Gigabit Ethernet" from further
> reading, and that
> understanding is consistent with what you say below. But then what does
> Ettus mean
> by "Dual 1 Gigabit Ethernet"?
>
> Thanks again,
>
> C
>
> On Thu, 2017-11-16 at 17:08 -0800, Neel Pandeya wrote:
>
> Hello Chad:
>
> If you are using 1 Gigabit Ethernet, then only one of two SFP ports in the
> rear of the X300/X310 can be used. If you have 10 Gigabit Ethernet, then
> the second SFP port can be used. Please see the link below. The SFP ports
> are configured depending on which FPGA image is being used.
>
> http://files.ettus.com/manual/page_usrp_x3x0.html#x3x0_load_
> fpga_imgs_fpga_flavours
>
> Regarding your use-case, if you have a second daughterboard in your
> X300/X310, then you can simultaneously receive in parallel. With two
> daughterboards, the X300/X310 provides two transmit chains and two receive
> chains.
>
> What is the configuration of your system?
>
> --Neel Pandeya
>
>
>
> On 15 November 2017 at 17:34, Chad Spooner via USRP-users <
> usrp-users at lists.ettus.com> wrote:
>
> All:
>
> I'm wondering how to use the second ethernet port on my x310. I've been
> going through the
> online Ettus SDR help, but can't seem to find the right pages.
>
> The short version of my question is: Can I use the two ethernet ports
> independently, say
> when each of them is connected to a separate computer? If so, how do I set
> up the second
> port? I'm using computers with 1 GiG Ethernet only.
>
> Details/Context: I have a working gnuradio companion flowgraph that
> generates a signal indefinitely
> and applies it to (A:0, Tx/Rx). That output port is connected by a cable
> to (B:0, RX2).  All indications are
> that this is working well. At irregular intervals, I want to obtain large
> numbers of samples from
> (B:0, RX2) by calling, say, uhd_rx_cfile or the like, outside of the
> flowgraph, which is still
> running. I'm prevented from doing that while the flowgraph is running. Can
> I do it using the
> second 1 GiG port if I set it up properly?
>
> Thanks for any advice you can offer.
>
> Chad
>
> --
> Chad M. Spooner
> NorthWest Research Associates
> 301 Webster Street
> Monterey, CA 93940cmspooner at nwra.com831 582 4904 <(831)%20582-4904>
> cyclostationary.blog
>
>
> _______________________________________________
> USRP-users mailing list
> USRP-users at lists.ettus.com
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
>
> --
> Chad M. Spooner
> NorthWest Research Associates
> 301 Webster Street
> Monterey, CA 93940cmspooner at nwra.com831 582 4904 <(831)%20582-4904>
> cyclostationary.blog
>
>
>
> --
> Chad M. Spooner
> NorthWest Research Associates
> 301 Webster Street
> Monterey, CA 93940cmspooner at nwra.com831 582 4904 <(831)%20582-4904>
> cyclostationary.blog
>
>
> _______________________________________________
> USRP-users mailing list
> USRP-users at lists.ettus.com
> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/attachments/20171117/b0bc3969/attachment-0002.html>


More information about the USRP-users mailing list