Basic Example from PythonSupport page fails with RuntimeError: setFrequency failed

[RDPowerz]

So, I copied/pasted the Basic Example from https://github.com/pothosware/SoapySDR/wiki/PythonSupport into a file and ran it, and it failed. Here is the output:

Found Rafael Micro R820T tuner
{default_input=True, default_output=True, device_id=0, driver=audio, label=hw:HDA Intel PCH,0}
{default_input=False, default_output=False, device_id=13, driver=audio, label=default}
{driver=remote, label=AirSpy HF+ [3652eb5dacde39f8], remote=tcp://192.168.1.22:55132, remote:driver=airspyhf, serial=3652eb5dacde39f8}
{driver=rtlsdr, label=Generic RTL2832U OEM :: 00000001, manufacturer=Realtek, product=RTL2838UHIDIR, serial=00000001, tuner=Rafael Micro R820T}
[INFO] Opening Generic RTL2832U OEM :: 00000001...
Found Rafael Micro R820T tuner
('RX',)
('TUNER',)
2.3999e+07, 1.764e+09
Exact sample rate is: 1000000.026491 Hz
[R82XX] PLL not locked!
Traceback (most recent call last):
  File "/tmp/x.py", line 22, in <module>
    sdr.setFrequency(SOAPY_SDR_RX, 0, 912.3e6)
  File "/usr/local/lib/python2.7/dist-packages/SoapySDR.py", line 1866, in setFrequency
    return _SoapySDR.Device_setFrequency(self, *args)
RuntimeError: setFrequency failed

I think 'PLL not locked!' is a clue. I vaguely recall some issue with rtlsdr that only certain sample rates can be set and frequency values could be tuned, but it seems the ones in the example are not working. My radio is a 'rtl-sdr.com v3' device purchased within the last year or so. so very mainstream, I would think.

Note I have been working in this code base for a week or two and have had success with using 'Softrock' radio with gqrx, see the Issues in SoapyAudio for some changes I suggested there.

Here is my environment. SoapySDR and the modules are all recent code I built from the git repos. Operating system is Ubuntu 18.04.

$ SoapySDRUtil --find
######################################################
##     Soapy SDR -- the SDR abstraction library     ##
######################################################

Found Rafael Micro R820T tuner
Found device 0
  default_input = True
  default_output = True
  device_id = 0
  driver = audio
  label = hw:HDA Intel PCH,0

Found device 1
  default_input = False
  default_output = False
  device_id = 13
  driver = audio
  label = default

Found device 2
  driver = remote
  label = AirSpy HF+ [3652eb5dacde39f8]
  remote = tcp://192.168.1.22:55132
  remote:driver = airspyhf
  serial = 3652eb5dacde39f8

Found device 3
  driver = rtlsdr
  label = Generic RTL2832U OEM :: 00000001
  manufacturer = Realtek
  product = RTL2838UHIDIR
  serial = 00000001
  tuner = Rafael Micro R820T

$ SoapySDRUtil --info
######################################################
##     Soapy SDR -- the SDR abstraction library     ##
######################################################

Lib Version: v0.8.0-g926c86d9
API Version: v0.8.0
ABI Version: v0.8
Install root: /usr/local
Search path:  /usr/local/lib/SoapySDR/modules0.8
Module found: /usr/local/lib/SoapySDR/modules0.8/libHackRFSupport.so   (0.3.3-7d53087)
Module found: /usr/local/lib/SoapySDR/modules0.8/libairspyhfSupport.so (0.1.1-b6cfbf5)
Module found: /usr/local/lib/SoapySDR/modules0.8/libaudioSupport.so    (0.1.1-9aa2b5c)
Module found: /usr/local/lib/SoapySDR/modules0.8/libremoteSupport.so   (0.6.0-c09b2f1)
Module found: /usr/local/lib/SoapySDR/modules0.8/librtlsdrSupport.so   (0.3.1-52cb5c0)
Available factories... airspyhf, audio, hackrf, remote, rtlsdr
Available converters...
 -  CF32 -> [CF32, CS16, CS8, CU16, CU8]
 -  CS16 -> [CF32, CS16, CS8, CU16, CU8]
 -  CS32 -> [CS32]
 -   CS8 -> [CF32, CS16, CS8, CU16, CU8]
 -  CU16 -> [CF32, CS16, CS8]
 -   CU8 -> [CF32, CS16, CS8]
 -   F32 -> [F32, S16, S8, U16, U8]
 -   S16 -> [F32, S16, S8, U16, U8]
 -   S32 -> [S32]
 -    S8 -> [F32, S16, S8, U16, U8]
 -   U16 -> [F32, S16, S8]
 -    U8 -> [F32, S16, S8]

[zuckschwerdt]

1M is fine as sample rate for the RTL-SDR. The SoapyRTLSDR version 52cb5c0 has changes to the error handling, which is what you see here. I'll take a look what went wrong.

[RDPowerz]

I'll take a look what went wrong.

Thanks for the quick response! I will await your findings.

[zuckschwerdt]

It's not an error after all. The message is from setting the frequency correction (PPM), rtlsdr_set_freq_correction results in -2 -- which is not an error code.. https://github.com/osmocom/rtl-sdr/blob/master/src/librtlsdr.c#L927 Hang on, I'll fix this now.

[zuckschwerdt]

Sorry for the trouble, that return code was really unexpected, shouldn't have missed that though.

[RDPowerz]

Not a problem!  Thank you for fixing it so quickly!

I was able to pull the changes from git, build the new version of SoapyRTLSDR, install it, run the example, and see that it is fixed. The only thing that does not seem right is "SoapySDRUtil --info" still reports the old commit hash in the version:

  Module found: /usr/local/lib/SoapySDR/modules0.8/librtlsdrSupport.so   (0.3.1-24b27fa) It should end with 'ed22', no? Yet the fix is working so I know the changed library has been installed. Do I need to rebuild the main SoapySDR directory for it to pick up the new version string from the library?

[zuckschwerdt]

You need to wipe the build directory for SoapyRTLSDR, or at least the build/Version.cpp file, then rebuild and install librtlsdrSupport.so to get the correct version tag shown.

[RDPowerz]

Thank you, I see my mistake now. By the way I uploaded an extended Python SoapySDR example program at https://github.com/RDPowerz/SoapyPythonExamples along with its output for three radios I have access to.  It is free for anyone to use as they see fit. Regards,RDP

[guruofquality]

You need to wipe the build directory for SoapyRTLSDR, or at least the build/Version.cpp file, then rebuild and install librtlsdrSupport.so to get the correct version tag shown.

Just FYI The cmake build extracts the info from git and puts it into the file. Simply pulling the repo wont cause cmake to re-run (unless there were CMakeLists.txt changes). You can touch CMakeCache.txt or rerun cmake to get the same effect.

[RDPowerz]

Hi, Josh. I raised an issue ( https://github.com/pothosware/SoapyAudio/issues/16 ) against SoapyAudio that includes a suggested patch to address the issue.  I'm wondering if that issue is being considered, and am wondering if a pull request would be helpful. Regards,RDP On Sunday, December 13, 2020, 12:06:58 PM EST, Josh Blum notifications@github.com wrote:

You need to wipe the build directory for SoapyRTLSDR, or at least the build/Version.cpp file, then rebuild and install librtlsdrSupport.so to get the correct version tag shown.

Just FYI The cmake build extracts the info from git and puts it into the file. Simply pulling the repo wont cause cmake to re-run (unless there were CMakeLists.txt changes). You can touch CMakeCache.txt or rerun cmake to get the same effect.

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or unsubscribe.

[guruofquality]

The hamlib stuff was sort of tacked on, and it seems to be pretty specific to certain devices. Im not very familiar with it, but yes, a PR would be helpful. I'm happy to have it.

[RDPowerz]

Thanks, Josh.  I did try to code defensively i.e. tried hard to not break any existing functionality.   I will send a PR some time in the next few days depending on when I get a chance to do it. Regards,RDP On Monday, December 28, 2020, 06:57:09 PM EST, Josh Blum notifications@github.com wrote:

The hamlib stuff was sort of tacked on, and it seems to be pretty specific to certain devices. Im not very familiar with it, but yes, a PR would be helpful. I'm happy to have it.

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or unsubscribe.

[RDPowerz]

Three months late, but I did just send a pull request last night...