Proper usage of 'daqdocfft' in embedded matlab

I am trying to apply MAP weighting onto data acquired from the 'analog input' block in embedded matlab setup.

The analog input block with a sampling rate = 16000, block size = 5, signal type = sample based and Asynchronous acquisition is used. This is then fed to the embedded matlab block where I have the following code.

function uMap  = mapWeighting(u)
%#eml

% Some Declarations and initializations to avoid 'mxArray' related errors
i = 0; TL = 0; uFL = 0; 
Fs = 16000;
T = zeros(40000,1);
uF = zeros(40000,1);
uMAG = zeros(40000,1);
uMAG_MAP = zeros(40000,1);
% aData = zeros(5,1); OR aData = zeros(80000,1); OR aData = zeros(size(u));
% aData = u;

eml.extrinsic('daqdocfft','length');
[uF,uMAG] = daqdocfft(u,Fs,5*Fs);
% [uF,uMAG] = daqdocfft(u,Fs,5*Fs);

% Use for loops to get rid of the errors due to the vector operations here
uFL = length(uF);

for i = 1 : uFL
    T(i) = ( 3.64 * ((uF(i)/1000)^-0.8) ) ...
    - ( 6.5 * exp(-0.6 * ((uF(i)/(1000-3.3))^3)) ) ...
    + ( 10^-3 * ((uF(i)/1000)^4) );
end

% Finally apply the weighting T onto the magnitude of the recorded samples
TL = length(T);
for j = 1 : TL
    uMAG_MAP(j) = uMAG(j) * T(j);
end

% Assignment to the return variable 'uMap'
uMap = uMAG_MAP;

When I run this, I get the following error,

---------------------------------------------------------------

Embedded MATLAB Interface Error: Call to MATLAB function aborted: Index exceeds matrix dimensions. Block Embedded MATLAB Function (#28) While executing: none.

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I fail to understand, what the problem here is?

I tried to use an intermediate variable and assign the values of input 'u' to it, so that I can explicitly give the details of the dimensions.

Using,

1) aData = zeros(5,1) or zeros(size(u)) --> gives the same error as above.

2) aData = zeros(80000,1) --> gives a size mismatch error shown below

-------------------------------------------------------------

Size mismatch (size [80000 x 1] ~= size [5 x 1]). The size to the left is the size of the left-hand side of the assignment.

-------------------------------------------------------------

The code works fine, if I remove the analog input block and make and extrinsic call to 'wavread' a file and perform the operations.

--Things to know--

MATLAB 32-bit version running on 64-bit Windows 7 (Please let me know if there is anything else needed to know)

What am I missing here or doing wrong?

Please guide. Many thanks in advance.