AWR2243: some Questions about reading radar echo data codes

Dear engineers， when I reading the AWR2243 radar echo data, the code understanding is not deep enough, please help to answer, thank you .

The code path of the cascade radar to read data is: ~:\ti\mmwave_studio_03_00_00_14\mmWaveStudio\MatlabExamples\4chip_cascade_MIMO_example\utils\dataParse\read_ADC_bin_TDA2_separateFiles

What are the parameters frameIdx and numLoops?

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%% read raw adc data with MIMO 

function [radar_data_Rxchain] = read_ADC_bin_TDA2_separateFiles(fileNameCascade,frameIdx,numSamplePerChirp,numChirpPerLoop,numLoops, numRXPerDevice, numDevices)


  dataFolder =fileNameCascade.dataFolderName;
  fileFullPath_master = fullfile(dataFolder,fileNameCascade.master);
  fileFullPath_slave1 = fullfile(dataFolder,fileNameCascade.slave1);
  fileFullPath_slave2 = fullfile(dataFolder,fileNameCascade.slave2);
  fileFullPath_slave3 = fullfile(dataFolder,fileNameCascade.slave3);

 [radar_data_Rxchain_master] = readBinFile(fileFullPath_master, frameIdx,numSamplePerChirp,numChirpPerLoop,numLoops, numRXPerDevice, numDevices);
 [radar_data_Rxchain_slave1] = readBinFile(fileFullPath_slave1, frameIdx,numSamplePerChirp,numChirpPerLoop,numLoops, numRXPerDevice, numDevices);
 [radar_data_Rxchain_slave2] = readBinFile(fileFullPath_slave2, frameIdx,numSamplePerChirp,numChirpPerLoop,numLoops, numRXPerDevice, numDevices);
 [radar_data_Rxchain_slave3] = readBinFile(fileFullPath_slave3, frameIdx,numSamplePerChirp,numChirpPerLoop,numLoops, numRXPerDevice, numDevices);

% Arranged based on Master RxChannels, Slave1 RxChannels, slave2 RxChannels, slave3 RxChannels 
% The RX channels are re-ordered according to "TI_Cascade_RX_ID" defined in
% "module_params.m"
 radar_data_Rxchain(:,:,1:4,:) = radar_data_Rxchain_master;
 radar_data_Rxchain(:,:,5:8,:) = radar_data_Rxchain_slave1;
 radar_data_Rxchain(:,:,9:12,:) = radar_data_Rxchain_slave2;
 radar_data_Rxchain(:,:,13:16,:) = radar_data_Rxchain_slave3;
        
end


function [adcData1Complex] = readBinFile(fileFullPath, frameIdx,numSamplePerChirp,numChirpPerLoop,numLoops, numRXPerDevice, numDevices)
Expected_Num_SamplesPerFrame = numSamplePerChirp*numChirpPerLoop*numLoops*numRXPerDevice*2;
fp = fopen(fileFullPath, 'r');
fseek(fp,(frameIdx-1)*Expected_Num_SamplesPerFrame*2, 'bof');
adcData1 = fread(fp,Expected_Num_SamplesPerFrame,'uint16');
neg             = logical(bitget(adcData1, 16));
adcData1(neg)    = adcData1(neg) - 2^16;
%% 
adcData1 = adcData1(1:2:end) + sqrt(-1)*adcData1(2:2:end);
adcData1Complex = reshape(adcData1, numRXPerDevice, numSamplePerChirp, numChirpPerLoop, numLoops);
adcData1Complex = permute(adcData1Complex, [2 4 1 3]);
fclose(fp);
end