Forum: GNU Radio Questions on callback functions implementation of blocks in gr-trellis

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Zhe Feng (Guest)
on 2014-05-03 08:33
(Received via mailing list)
Hi all,

I'm working on a system with trellis coding and I met a problem with the
python callback function generated by grc . Because there are several
parameters used in the blocks needs to be updated. I added callback
functions for those parameters in those c++ files.

For example, to add callback function for the FSM parameter in the
viterbi_combined block, I declared set_FSM function in
viterbi_combined.h ,
defined the function in viterbi_combined_impl.h, and added <callback>
set_FSM($FSM) </callback> in the viterbi_combined.xml file.

After that, I reinstalled the gnuradio and checked the
confirmed that python has linked these callback functions in the
viterbi_combined class.

But when I execute the grc application, this callback function wasn't
automatically generated in the resulting python file. After I added this
set_FSM function by myself, the flow graph worked as what I expected.

I've added callback functions for other blocks like repack_bits of
module. After I've done exactly the same thing, the callback function I
added was correctly generated in python file after I executed in grc.

So my question is: why these callback functions I added in gr-trellis
weren't automatically generated in python file after execution in grc
the other callbacks in gr-blocks? Did I do anything wrong?

I attached my modification on gnuradio in the patch file for your


Zhe patch.patch

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