[Discuss-gnuradio] Sampling slowly

[Mike Willis]

Looking for help

 

I have written a source block to do satellite predictions. It acts as a source of a float representing the input parameter – e.g. elevation. The block probes predict via UDP, looks at the string returned and selects the asked for parameter.

 

So far fine, but I would like to probe it slowly, not on every sample. This appears to be impossible. If I use a probe and function probe and ask it to update each second, the probe grabs data from the source runs at full sample rate. Unfortunately probe seems to have almost no documentation and I don’t understand the source but I assume it goes as fast as it can get input samples.

 

If I try combining say an add block with a decimated version of the sample rate (coming from a USRP) and probe again, it still runs too fast. It is as if it is trying to cache a set values. Logically I can see that might be useful to maintain a constant rate where blocks take different times.

 

Is there a simple fix or do I need to implement some form of trigger port – and if I do will it still cache data?

 

Mike