AD9361 (FMCOMMS3) No-OS with VC707 - Suitability for Resonant frequency search


I have been using the VC707 with a FMCOMMS3 board attached.  I am trying to determine the suitability of the AD9361 for our target application.  Currently I am trying to evaluate the ability of the device to create a continuous frequency sweep (beginning at f = 200MHz and finishing at f = 300MHz).  I am using the No-OS files contained here : GitHub - analogdevicesinc/no-OS: Software drivers for systems without OS 

I would just like to confirm some details about operation:

1. In the Config.h file I have uncommented DAC_DMA_EXAMPLE, so the output should be coming from sine_lut().  I have also read in past discussions that I can replace sine_lut() with my own values or even a new LUT with a different length.  I would like to know if it is OK for me to use a LUT I have defined called chirp_lut().  This LUT has a length of 32768 and contains datapoints for a twos complement chirp function.  My goal is to use this LUT as a 'sweep' function.  

2.  If I want to receive the data (i.e. I have transmitted and am going to receive the continuous data), my understanding is that I should modify adc_core.c to implement a 'double buffer scheme' for the DMA where the first buffer fills with data and while the second buffer is filling, the data from the first buffer is processed and prepared again for capture.  I am very much a hardware engineer and do not properly understand how to write the code to do this, I believe it shouldn't be too difficult, I just do not know where to start - Could you please offer some advice on this?

3. After using the SDK to run the configuration I have set up, do you have any advice for how I can build in 'triggers' for commencing a sweep or commencing another function?  Would this require a modification of the Main.c where I would create some form of input handlers?  Again, I am not a software engineer and these solutions are not obvious to me. 

If it helps, my overall goal is to attach a simple LC resonator circuit, transmit a sweep function and plot the reflected spectra which will be captured.  The goal is to determine the resonant frequency. 

Any advice would be greatly appreciated!



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