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    <div class="moz-cite-prefix">On 04/22/2015 02:05 PM, Marcus D. Leech
      via USRP-users wrote:<br>
    </div>
    <blockquote cite="mid:5537E2EF.1080206@ripnet.com" type="cite">
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      <div class="moz-cite-prefix">On 03/17/2015 01:55 PM, Hunter
        DeJarnette wrote:<br>
      </div>
      <blockquote
cite="mid:CAAs=sso94nwzEJMV17MMc1mAAnK3eAemHW6wgqwUi8dpkUoiUQ@mail.gmail.com"
        type="cite">
        <div dir="ltr">
          <div>
            <div>Marcus,<br>
              <br>
            </div>
            Thanks for your quick reply.  Is this supported on other
            USRP models?  Are there any plans for this to be supported
            on the B210?<br>
            <br>
          </div>
          Hunter<br>
        </div>
      </blockquote>
      No, there's no support for this in other models, either.  While
      it's conceptually possible, it isn't actually implemented,
      partially because there's<br>
        no way to setup the master clock (on, for example, the X310) in
      cases where there's no common master-clock rate that can produce
      both<br>
        sample rates.<br>
      <br>
      The best approach is to bring both streams in at the same rate,
      and resample the lower-rate stream.  If you use Gnu Radio, there
      are various<br>
        resamplers, including a rational and fractional resampler.<br>
      <br>
      <br>
    </blockquote>
    I was mis-lead by R&D, and have now been re-lead :)<br>
    <br>
    On the *X310 in particular*, you can have two different sample rates
    from the two "sides" but those streams *must* be packaged inside<br>
      separate multi_usrp objects,  and they both must, of course,
    satisfy the integer fraction rules with respect to the master clock
    rate.<br>
    <br>
    The streams inside a multi-usrp object are required to be at the
    same sample-rate, because a multi-usrp "object" does sample time<br>
      synchronization which is maximally awkward if the streams are
    running at two different rates....<br>
    <br>
    <br>
    <blockquote cite="mid:5537E2EF.1080206@ripnet.com" type="cite">
      <blockquote
cite="mid:CAAs=sso94nwzEJMV17MMc1mAAnK3eAemHW6wgqwUi8dpkUoiUQ@mail.gmail.com"
        type="cite">
        <div class="gmail_extra"><br>
          <div class="gmail_quote">On Tue, Mar 17, 2015 at 12:51 PM, <span
              dir="ltr"><<a moz-do-not-send="true"
                href="mailto:mleech@ripnet.com" target="_blank">mleech@ripnet.com</a>></span>
            wrote:<br>
            <blockquote class="gmail_quote" style="margin:0 0 0
              .8ex;border-left:1px #ccc solid;padding-left:1ex">
              <div
                style="font-size:10pt;font-family:Verdana,Geneva,sans-serif">
                <p>This is not a supported configuration on the B210.</p>
                <p>If you need different sample-rates on the two
                  streams, you'll have to re-sample in software.</p>
                <div>
                  <div class="h5">
                    <p> </p>
                    <p> </p>
                    <div> </div>
                    <p>On 2015-03-17 12:12, Hunter DeJarnette via
                      USRP-users wrote:</p>
                  </div>
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                <blockquote type="cite"
                  style="padding-left:5px;border-left:#1010ff 2px
                  solid;margin-left:5px">
                  <div>
                    <div class="h5">
                      <div dir="ltr">I'm working on an application with
                        the B210 where I would like to use both rx
                        dsp's, but at different sample rates. I
                        understand that each of the channels attached to
                        a single rx_streamer must have the same sample
                        rate. So to get around this issue I tried
                        instantiating two usrp sources each with a
                        different channel like so:
                        <p><span></span>        self.uhd_usrp_source_0 =
                          uhd.usrp_source(<br>
                                      ",".join(("type=b200", "")),<br>
                                      uhd.stream_args(<br>
                                          cpu_format="fc32",<br>
                                          channels=[0],<br>
                                      ),  <br>
                                  )   <br>
                                  self.uhd_usrp_source_1 =
                          uhd.usrp_source(<br>
                                      ",".join(("type=b200", "")),<br>
                                      uhd.stream_args(<br>
                                          cpu_format="fc32",<br>
                                          channels=[1],<br>
                                      ),  <br>
                                  )   <br>
                                 
                          self.uhd_usrp_source_0.set_subdev_spec("A:A
                          A:B", 0)<br>
                                 
                          self.uhd_usrp_source_0.set_samp_rate(samp_rate_0)<br>
                                 
                          self.uhd_usrp_source_1.set_samp_rate(samp_rate_1) </p>
                        <p>I found that when the sample rates for the
                          two sources are the same I get similar
                          performance to the using two channels on a
                          single usrp_source. However, when I try to use
                          different sample rates I start dropping
                          samples. Am I setting this up right?</p>
                        <p> </p>
                        <p>Thanks,</p>
                        Hunter</div>
                      <br>
                    </div>
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