[Discuss-gnuradio] detecting frequency with gr.goertzel_fc() in python

[Casey Halverson]

Hello, I have written a few static blocks in python, but i am still  
very much a beginner.

I want to be able to detect frequency of a single tone in gnuradio.  I  
have read that perhaps gr.goertzel_fc() is something I should use.    
However, the documentation is very vague and I am unsure how exactly I  
should even start using it, what 'len' means in its arguments, how i  
connect something to it, and what it outputs.   I am wondering if  
someone can point me in the right direction.  I have written a small  
test script using a sine wave generator as an example.   the end goal  
is to detect various tones to input into a state machine using the USRP.


Thank you!


---

#!/usr/bin/env python

from gnuradio import gr
from gnuradio import audio
import time

class my_top_block(gr.top_block):
    def __init__(self):
        gr.top_block.__init__(self)
        sample_rate = 32000
        ampl = 0.1
        src1 = gr.sig_source_f (sample_rate, gr.GR_SIN_WAVE, 1200,  
ampl)
        det = gr.goertzel_fc(32000,100??,1200)
        self.connect (src1, det, ????)

if __name__ == '__main__':
    try:
         my_top_block().run()
    except KeyboardInterrupt:
        pass