Discuss KerberosSDR - 4x Coherent RTL-SDR
3 posts • Page 1 of 1
I have a project that requires frequency changes every measurement. Since this needs a new calibration for each frequency, I made automated calibration boards controlled by the GPIO of the Raspberry Pi - so I can get new delay values for each frequency and then use those values for each frequency. That's fine, but after some time, the code hangs when reading the buffer. Eventually, I determined that the delays are added cumulatively in sync.c, and eventually, they exceed the buffer size. My question is, what is the purpose of this delay accumulation? For my application, would it make more sense to use fresh delay values each time, and not accumulate them?
I change frequencies, and thus set sampling delays, every 20 seconds, and recalibrate every 5 minutes. There are basically three scenarios: 1) accumulated delay is less than negative BUFFER_SIZE (fails) 2) accumulated delay value value exceeds BUFFER SIZE (fails) or 3) neither 1 or 2 (successful). Perhaps I could make the accumulated delay value modulo BUFFER_SIZE to circumvent these failures. Or set the delays within the python code after sampling, rather than through sync.