On 09/28/2019 06:17 PM, Andrew Payne via USRP-users wrote:
Hello,
I am writing a program in Python to interface with a simple file
source to USRP sink flowgraph.
I have a short IQ file that I simply want to play once without
repeating, and I want the calling Python code to "know" when it's
completed after commanding the GR class instance to start via a call
to tb.start(), if tb is the class instance variable. I came across
the C++ GR API here:
https://www.gnuradio.org/doc/doxygen/classgr_1_1block.html#a89242cb1ac9d2bf5e75f923745baa576
^ That shows there's a gr.finished() boolean return that tells you
when the flowgraph is done, but evidently .finished is not an
attribute of tb. The only methods that worked for me are
tb.start/tb.run, tb.wait, tb.stop.
I'd also be happy with polling the GR class instance for the
noutput_items from the work function of the USRP_sink block. I know
the file size so I can have a while loop with the noutput_items value
as a condition, but how do I do that in Python? I think I am getting
close with these 2 results from Google but still not getting it:
1)
https://stackoverflow.com/questions/50938245/gnuradio-number-of-output-items/50943105
2)
https://stackoverflow.com/questions/32305813/gnuradio-how-to-change-the-noutput-items-dynamically-when-writing-oot-block
Thanks,
Andrew
_______________________________________________
USRP-users mailing list
USRP-users@lists.ettus.com
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
I'll note that top_block is a special class, and the gr::block::finished
applies to "ordinary" blocks.
This type of question properly belongs on the discuss-gnuradio mailing
list, not here, since it is NOT peculiar to USRP hardware at all.
In the absence of anything better, my approach could branch into a
couple of different things:
o see how "top_block::wait" is implemented, and see if there's an
opportunity there
o watch the output file size using os.stat()
But again, this question is properly a Gnu Radio question, and not a UHD
question.
_______________________________________________
USRP-users mailing list
USRP-users@lists.ettus.com
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
