# Can't Control FCD Parameters **URL:** \ **Category:** GNU Radio\ **Created:** [February 17, 2013, 8:07pm UTC](https://www.ruby-forum.com/t/cant-control-fcd-parameters/226673 "2013-02-17T20:07:14Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![George\_SSWilliams](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/df705f/32.png) [@George\_SSWilliams](https://www.ruby-forum.com/u/George_SSWilliams)\ **Post date:** [February 17, 2013, 8:07pm UTC](https://www.ruby-forum.com/t/cant-control-fcd-parameters/226673/1 "2013-02-17T20:07:14Z")
I have installed 3.6.3 (from source) on a fresh install of Scientific Linux 6.3. I basically followed the build instructions on the Fedora page on the wiki after I added the EPEL repo to yum. ‘make’ and ‘make install’ ran without errors. ‘make test’ did not complete- it hung at ‘27/179 Testing qa\_pdu’(Is there any way to bypass this particular test to complete the remaining tests?) This problem I am having is that I can’t change any of the FCD parameters. I can hear audio from the device, but I can’t change the frequency either from a control widget or by changing it in the FCD block in GRC. The flow graph works properly on another computer, running an older gnuradio, using the same FCD. I’m looking for any ideas as to what I might have missed. Thanks, George ---
**Author:** ![George\_SSWilliams](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/df705f/32.png) [@George\_SSWilliams](https://www.ruby-forum.com/u/George_SSWilliams)\ **Post date:** [February 17, 2013, 10:08pm UTC](https://www.ruby-forum.com/t/cant-control-fcd-parameters/226673/2 "2013-02-17T22:08:47Z")
On Sun, Feb 17, 2013 at 10:26 AM, George S. Williams [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)wrote: > from a control widget or by changing it in the FCD block in GRC. > > The flow graph works properly on another computer, running an older > gnuradio, using the same FCD. Thanks for letting us know about this, but without more information, it is difficult to help you. What is the ‘older’ version of GNU Radio where this works? What OS is that computer? Can you post a link to the .grc files for both? The qa\_pdu bug is known about but not yet fixed. You can exclude it by running ‘ctest -E qa\_pdu’ instead of ‘make test’. See ‘man ctest’ for more details. Johnathan ---
**Author:** ![George\_SSWilliams](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/df705f/32.png) [@George\_SSWilliams](https://www.ruby-forum.com/u/George_SSWilliams)\ **Post date:** [February 17, 2013, 10:15pm UTC](https://www.ruby-forum.com/t/cant-control-fcd-parameters/226673/3 "2013-02-17T22:15:13Z")
On Sun, Feb 17, 2013 at 7:26 PM, George S. Williams [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > a control widget or by changing it in the FCD block in GRC. > > The flow graph works properly on another computer, running an older > gnuradio, using the same FCD. > > I’m looking for any ideas as to what I might have missed. Does qthid work? If not maybe you forgot to put the funcube-dongle.rules files into /etc/udev/rules.d/ Alex ---
**Author:** ![George\_SSWilliams](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/df705f/32.png) [@George\_SSWilliams](https://www.ruby-forum.com/u/George_SSWilliams)\ **Post date:** [February 18, 2013, 4:10pm UTC](https://www.ruby-forum.com/t/cant-control-fcd-parameters/226673/4 "2013-02-18T16:10:04Z")
Alex and Johnathan, Thanks for the replies and the tip. The problem was with my udev rule, not with gnuradio. George ---
**Author:** ![George\_SSWilliams](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/df705f/32.png) [@George\_SSWilliams](https://www.ruby-forum.com/u/George_SSWilliams)\ **Post date:** [February 18, 2013, 5:36pm UTC](https://www.ruby-forum.com/t/cant-control-fcd-parameters/226673/5 "2013-02-18T17:36:02Z")
That’s good to know, thanks for the update. I hope this part will be easier in the future when we change gnuradio to use libfcd. Alex