Pfb_decimator_ccf(13): insufficient connected input ports (5 needed, 1 connected)

GNU Radio
1

Hi, all

     I try to re-structure the osmo-tetra to work with GNU Radio

3.7. The osmo-tetra is based on GNU Radio 3.6.

     The original code has tuner, resampler, demodulater three

modules which connected sequentially.

     The resampler is based on function pfb_decimator_ccf which

changes from 3.6 to 3.7. The pfb_decimator_ccf only take single
parameter decimation, which changes in 3.7,

     After reading the manual of 3.7, I made following changes to

the python script :

    Add a low-pass filter " taps = filter.firdes.low_pass_2(1, fs,

options.low_pass, options.low_pass * 0.2, attenuation_dB=ATT,
window=filter.firdes.WIN_BLACKMAN_hARRIS) "

Change "self.resamp = blks2.pfb_decimator_ccf(int(rerate)) " to "
self.resamp = filter.pfb_decimator.ccf(int(rerate), taps, 0) "

But error still occurs when connecting modules " self.connect(self.src,
self.tuner, self.resamp, self.demod, self.output) " :

Traceback (most recent call last):
File “./osmosdr-tetra_demod_fft.py”, line 264, in
tb.Run(True)
File
“/usr/local/lib/python2.7/dist-packages/grc_gnuradio/wxgui/top_block_gui.py”,
line 82, in Run
self.Start(start, max_nouts)
File
“/usr/local/lib/python2.7/dist-packages/grc_gnuradio/wxgui/top_block_gui.py”,
line 73, in Start
self.start()
File
“/usr/local/lib/python2.7/dist-packages/gnuradio/gr/top_block.py”, line
103, in start
top_block_start_unlocked(self._tb, max_noutput_items)
File
“/usr/local/lib/python2.7/dist-packages/gnuradio/gr/runtime_swig.py”,
line 4612, in top_block_start_unlocked
return _runtime_swig.top_block_start_unlocked(*args, **kwargs)
RuntimeError: pfb_decimator_ccf(13): insufficient connected input ports
(5 needed, 1 connected)

     Does it indicate pfb_decimator_ccf take 5 inputs ? It puzzled

me.

Best Regards, Jiang Pin

2

On 09.02.2014 07:39, JIANG Pin A wrote:

Hi, all

      I try to re-structure the osmo-tetra to work with GNU Radio

3.7. The osmo-tetra is based on GNU Radio 3.6.

OK, don’t know about osmo-tetra but…

RuntimeError: pfb_decimator_ccf(13): insufficient connected input ports
(5 needed, 1 connected)

      Does it indicate pfb_decimator_ccf take 5 inputs ? It puzzled me.

…the pfb_decimator takes 1 input. Not sure what’s going on there.

MB

3

On Sun, Feb 9, 2014 at 5:24 PM, Martin B. [email protected]
wrote:

MB
Actually, this is a bit of a tricky one, though it hasn’t changed in a
while. Basically, because we insert samples into each filter of the
filterbank consecutively, we’re performing the role of the
stream_to_streams block. Instead of duplicating that work, the
pfb_decimator and pfb_channelizer actually take M input streams (where
M is the number of channels or amount of decimation). Also, this
allows us to use the more efficient fir_filter blocks that expect a
data stream of continuous samples.

There are wrappers in Python for this in the filters.pfb module where
the stream_to_streams block is in there for you, so
filter.pfb.decimator_ccf takes only 1 input, but a
filter.pfb_decimator_ccf block would take M inputs.

Tom