%%% Script for reordering DCA1000 LVDS stream with 2 lanes
%%% capture format can be found in mmWave Studio User's Guide 22.8./9.

function [retVal] = readDCA(fileName, numFrames)
%% global variables
% change based on sensor config
%----------------------------------------------------------------------
numADCBits = 16; % number of ADC bits per sample
numADCSamples = 256; % number of ADC samples per chirp
numRx = 4; % number of receivers
chirpSize = numADCSamples*numRx;
%numFrames = 1; % is function input
loops = 32; % # of loops over chirp indices
numLanes = 2; % do not change. number of lanes is always 2
isReal = 0; % set to 1 if real only data, 0 if complex data0
isDemo = 1; % filter frame leading info
%-----------------------------------------------------------------------
%% read file
% read .bin file
fid = fopen(fileName,'r');
adcData = fread(fid, 'int16');
fclose(fid);
fileSize = size(adcData, 1);
% one chirp only
%adcData = adcData(1:chirpSize,1);
%% organize data by LVDS lane
% for real data, each Rx in column
if isReal
    LVDS = zeros(1, length(adcData(:,1)));
    LVDS = reshape(adcData(:,1), [], numRx);
else
% for complex data
% LVDS row /w half length
% cmplx matrix /w real and imaginary row
    LVDS = zeros(1, length(adcData(:,1))/2);
    cmplx= zeros(2, length(adcData(:,1))/2);
% combine real and imaginary parts
    counter = 1;
    for i=1:4:fileSize-1
            LVDS(1,counter)     = adcData(i) + sqrt(-1)*adcData(i+2);
            LVDS(1,counter+1)   = adcData(i+1)+sqrt(-1)*adcData(i+3);
            cmplx(1,counter)    = adcData(i);
            cmplx(2,counter)    = adcData(i+2);
            cmplx(1,counter+1)  = adcData(i+1);
            cmplx(2,counter+1)  = adcData(i+3);
            counter = counter + 2;
    end
    % create column for each Rx channel
    % LVDS has numRx complex columns
    % cmplx has numRx real and numRx imaginary columns
    % for example numRx=4: 1-4 real, 5-8 imaginary
    if numRx > 2
    LVDS = reshape(LVDS(1,:), length(LVDS(1,:))/numRx, numRx);
    cmplx = cmplx.';
    cmplx = reshape([cmplx(:,1);cmplx(:,2)], length(cmplx(:,1))/numRx, 2*numRx);
    end
end
%% filter leading 0 frame from Demo Visualizer Capture
% Chirp profile information at beginning (of each frame)
if isDemo
    cmplx(1:loops/2,:)=[];
    for i=1:1:numFrames-1
        row = i*numADCSamples*loops;
        cmplx(row+1:row+loops/2,:)=[];
    end
end
%% organize data by chirps
% 

%% return receiver data
if isReal 
    retVal = LVDS;
else
    retVal = cmplx;
end