Forum: GNU Radio Oscope sink + small sample source file

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Ad81d1e6e8493baa75befee55a8dce64?d=identicon&s=25 Jeffrey Karrels (Guest)
on 2007-07-10 21:48
(Received via mailing list)
Hello all

Let me try and explain my issue.

I have a file source connected to a filter and a scope sink.  I see
that my scope only displays data if the source file is size x or
greater. (around 2100 samples in my case). In cases where the input
source file is smaller than x I get a blank (white) scope screen.  Can
someone explain to me what is going on there? Is there a way to
display smaller files? (or do I just have an error in my methodology?)


sps  = usrp_rate / options.decim_rate

#Setup scopes
self.scope1 = scopesink.scope_sink_f(self, panel, sample_rate=sps)


#Data source files
signal_src = gr.file_source(gr.sizeof_gr_complex, options.signal_file)

#Filter Signal Data
xtaps_signal = gr.firdes.low_pass(1.0, sps, filter_cutoff,

xfilter_signal = gr.freq_xlating_fir_filter_ccf(1, xtaps_signal, offset,

c2r1 = gr.complex_to_real()

self.connect(xfilter_signal, c2r1, (self.scope1,0))
3596cfe1d579c65b9babd35e8787977c?d=identicon&s=25 Matt Ettus (Guest)
on 2007-07-10 21:58
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The scope does not display every sample.  It only redraws at about 20 or
25 Hz as I remember, and is really only intended for continuous streams
of data.

Ad81d1e6e8493baa75befee55a8dce64?d=identicon&s=25 Jeffrey Karrels (Guest)
on 2007-07-10 22:15
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I guess I have MATLAB on this machine for a reason... Maybe I should use

Ae6772ccc21c2816e80124cb3ab1502c?d=identicon&s=25 Justin Shaw (Guest)
on 2007-07-11 00:27
(Received via mailing list)
...or matplotlib, see
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