Oscillator running out of sync
Hey guys,
I'm having a problem with the oscillator mode. We are using the SPECTRAN v6 version, and when we put the oscillator on, it runs okay for a couple of hours, and then it switches to this mode where it is offset by 44 us and never comes back. Restarting the connection to the device doesn't help, and it eventually goes to this state again.
Config which we are using is:
"main/centerfreq", "3.050e+09" "main/transgain", "-30" "device/receiverchannel", "Rx1+Rx2" "device/outputformat", "iq" "device/receiverclock", "122MHz" "calibration/preamp", "Both" "device/sclksource", "Oscillator" If any of these settings don't make sense, don't hesitate to point it out. Thanks a lot for help!
If you want to ensure that Rx1 and Rx2 are in perfect synch, use the interleave mode "Rx12" in which you get sample pairs from Rx1 and Rx2 in the same packet.
``` if (AARTSAAPI_ConfigFind(&d, &root, &config, L"device/receiverchannel") == AARTSAAPI_OK)
AARTSAAPI_ConfigSetString(&d, &config, L"Rx12");```
If you want to continue using the "Rx1+Rx2" mode, there is no guarantee that a USB packet loss may have different effects on the two channels. They may end up being out of synch, and it may take some time to resynch. You can force a faster resynch with the
/device/transmitterclockvar
setting. This is per default set to 0.0002 (200us) offset for a fast recovery. You can lower this to 1.0e-6 for an immediate recovery. The 44us offset matches the size of one USB transfer buffer, so it is most likely the result of a packet loss due to USB congestion.
If your application requires perfect synch of Rx1 and Rx2 the interleaved mode is the way to go.
Thanks a lot for the quick reply!
I've written to this other topic https://v6-forum.aaronia.de/forum/topic/what-may-i-assume-regarding-2-channel-keeping-up-in-time/
Could you provide me with a simple sample code from which you can retrieve data from Aaronia?
As of now, I've tried to set the mode to Rx12 and haven't observed any change in packet length or the number of data samples, where I expect it to grow to double the length.
Have a wonderful day!
