Re: AttributeError: module 'gnuradio.digital.qam' has no attribute 'qam_mod'

Hi Lannan -

Once again, please do NOT send me private email. Send all replies to

   discuss-gnuradio@gnu.org

gr-iio is NOT part of gnuradio radio - it just uses gnuradio, that is, it's a OOT module.

You MUST contact the author of the gr-iio module if you're having trouble with it.  I don't know anything about gr-iio.

-- Cinaed

On 6/17/20 3:36 PM, lannan jiang wrote:

Hi Cinaed,

   Thank you so much for your response.

   I realized that QAM mod and demod blocks were depreciated, so I tried contellation modulator instead. However, the error i get becomes the following:

 

Traceback (most recent call last):

  File "/home/lannanjiang/gr-iio/My_Radio/QAMmodem.py", line 209, in <module>

    main()

  File "/home/lannanjiang/gr-iio/My_Radio/QAMmodem.py", line 187, in main

    tb = top_block_cls()

  File "/home/lannanjiang/gr-iio/My_Radio/QAMmodem.py", line 138, in __init__

    self.digital_constellation_modulator_1 = digital.generic_mod(

  File "/usr/lib/python3/dist-packages/gnuradio/digital/generic_mod_demod.py", line 115, in __init__

    self.pre_diff_code = pre_diff_code and self._constellation.apply_pre_diff_code()

AttributeError: 'int' object has no attribute 'apply_pre_diff_code'

Additionally, python3 files were generated when I run my flow graphs, so i think that the compatibility with GNU 3.8 is not an issue?

Thanks in advance,

Lannan Jiang

---

From: Discuss-gnuradio <discuss-gnuradio-bounces+jln925=live.com@gnu.org> on behalf of Cinaed Simson <cinaed.simson@gmail.com>
Sent: Wednesday, June 17, 2020 5:39 PM
To: discuss-gnuradio@gnu.org <discuss-gnuradio@gnu.org>
Subject: Re: AttributeError: module 'gnuradio.digital.qam' has no attribute 'qam_mod'

 

Hi Lannan - gr-iio is an OOT (Out Of Tree) module and not part of GNU Radio. Unless someone on the list already has it working you're better off contacting the author.

Also, I took a quick look at the the cmake module "GrPython.cmake" and it appears to be searching for python2 so if it's not using python3 then it's possible the gr-iio module may not play well with GNU Radio 3.8.

If you want you could post your GRC file, we can look at to see if there any problems with flow but it's unlikely we can help you with gr-iio.

Under GNU radio 3.8, the QAM-mod and QAM-demod blocks have bee depreciated - which means either they don't work correctly under 3.8 or they can't be fixed to work under 3.8.

-- Cinaed

On 6/17/20 10:40 AM, lannan jiang wrote:

Hi everyone,

    I am still pretty new to GNU Radio, and I am trying to use the 'QAM-mod' block in GRC. However, I have encountered the following error and I am not sure how to fix this:

error message:

Traceback (most recent call last):

  File "/home/lannanjiang/gr-iio/My_Radio/QAMmodem.py", line 214, in <module>

    main()

  File "/home/lannanjiang/gr-iio/My_Radio/QAMmodem.py", line 192, in main

    tb = top_block_cls()

  File "/home/lannanjiang/gr-iio/My_Radio/QAMmodem.py", line 140, in __init__

    self.digital_qam_mod_2 = digital.qam.qam_mod(

AttributeError: module 'gnuradio.digital.qam' has no attribute 'qam_mod'

 The following is what I typed to install gnuradio and gr-iio on a 64bit guest machine, Ubuntu 20.04 LTS. 

  

  sudo apt install gnuradio

  sudo apt install swig

  sudo apt install liborc-dev

  git clone -b upgrade-3.8 https://github.com/analogdevicesinc/gr-iio.git

  cd gr-iio

  cmake .

  make

  sudo make install

  cd ..

  sudo ldconfig

I have looked up similar questions asked by others but I was unable to resolve this error.

   By the way, I was able tp use FM mod and demod blocks GNU radio, but I keep getting the "no attribute error" for QAM mod and constellation modulator blocks.

 Please help me with this, any suggestions will be appreciated!

Thanks in advance

Lannan Jiang