AD9361+ZedBoard+fmcomms3 remote linux host

Hello, I'm newbie in GNU Radio and Analog devices, I'm trying tu run the fm-transmitter example script on a linux host machine but i cant get the Zedboard to do anything.

I Have succesfully compiled and installed gnuradio using pybombs, libiio, libad9361-iio, gr-iio and iio oscilloscope using this instructions GNU Radio [Analog Devices Wiki] .

The iio oscilloscope works perfectly on the linux host machine connecting to the zedboard via LAN, but when i try to execute the GNU radio scripts the only error I get is "Error:failed to enable real-time scheduling." and the script seems to execute but it doesn't do anything on the Zedboard.

I'm attaching an image of my sink configuration, I hope anyone can help me with my problem.

Thanks.

Isaac

  • 0
    •  Analog Employees 
    on Jan 20, 2018 12:54 AM over 3 years ago

    This error "Error:failed to enable real-time scheduling" is fine and can be ignored.

    Can you try the "cyclic-sine" example first.  It is less dependent on other components like your sound card.

    Also the minimum RF bandwidth is 200kHz.

    -Travis

  • First of all thank you very much for helping me out! I really appreciate it, I cant run the flowgraph beacuase of this error:

    Error 0:
    Connection (
      Block - blocks_float_to_short_0 - Float To Short(blocks_float_to_short)
        Source - out(0)
      Block - iio_fmcomms2_sink_0 - FMComms2/3/4 Sink(iio_fmcomms2_sink)
        Sink - in0(0)
    ):
      Source IO size "2" does not match sink IO size "8".

    Error 1:
    Connection (
      Block - blocks_float_to_short_0_0 - Float To Short(blocks_float_to_short)
        Source - out(0)
      Block - iio_fmcomms2_sink_0 - FMComms2/3/4 Sink(iio_fmcomms2_sink)
        Sink - in1(1)
    ):
      Source IO size "2" does not match sink IO size "8".

    Error 2:
    Connection (
      Block - iio_fmcomms2_source_0 - FMComms2/3/4 Source(iio_fmcomms2_source)
        Source - out0(0)
      Block - blocks_short_to_float_0 - Short To Float(blocks_short_to_float)
        Sink - in(0)
    ):
      Source IO size "8" does not match sink IO size "2".

    Error 3:
    Connection (
      Block - iio_fmcomms2_source_0 - FMComms2/3/4 Source(iio_fmcomms2_source)
        Source - out1(1)
      Block - blocks_short_to_float_0_0 - Short To Float(blocks_short_to_float)
        Sink - in(0)
    ):
      Source IO size "8" does not match sink IO size "2".

    I googled the error and i cant find where to change the type so the colors match like it said on this link  Real cheap Software Defined Radios, part 3 | Richard WM Jones 

    I'm attaching an image of the flowgraph for you to have more information about the error.

    Thank you so much for your time and patience I'm very new to all this and it is taking me some time to learn.

    -Isaac

  • 0
    •  Analog Employees 
    on Jan 20, 2018 2:55 AM over 3 years ago

    The current version of that example flowgraph is a bit different: gr-iio/cyclic-sine.grc at master · analogdevicesinc/gr-iio · GitHub 

    The FMComms blocks have complex inputs now so you don't need the "Short To Float", "Float To Complex" and similar blocks on the transmit side.  The red connections in the flowgraph mean something is wrong.

    -Travis

  • It runs without any issue, i see the FFT and everything seems to be ok.

    When i run the fm-transmitter.grc (i also downloaded it from gr-iio/fm-transmitter.grc at master · analogdevicesinc/gr-iio · GitHub ), a terminal opens with a promt for exit, but when i try to listen to it with an sdr running in another computer I dont hear anything here is an image of the flowgraph

  • 0
    •  Analog Employees 
    on Jan 20, 2018 4:30 AM over 3 years ago

    I think the Sample rate on the radio is twice what you want since the output of the resampler is 1.152MHz, unless you are oversampling on purpose.

    You should also be able to receive true FM from a nearby station with the receiver flowgraph.  You might want to try and do that first then use the transmitter flowgraph.

    -Travis