MATLAB: Do I receive the error message ‘Initialization commands cannot be evaluated’ while executing the Output Port block in RF Blockset 2.3 (R2008b)

blockcommandsinitializationoutputportRFRF Toolbox

I have an RF blockset which consists of the S-parameters mixer and an Output Port block. When I execute the model, I receive an error stating:

 Initialization commands cannot be evaluated.

Best Answer

This enhancement has been incorporated in Release (R2010b). For previous product releases, read below for any possible workarounds:

This error occurs when the signal sampling rate, center frequency and the local oscillator (LO) frequency does not satisfy this relation:

    LO <= CF - 0.5*(1/ST)

where

    LO = Local Oscillator frequency
    CF = Center frequency
    ST = Sample Time.

fc - lo -fs/2 = -19424000

In the model, if the frequency generated is negative, this error will occur. To fix this error, please make sure you choose values for FC, LO and FS in such a manner that the above relation is satisfied.

Related Solutions

MATLAB: Where can I find more information about the implementation of the General Mixer block in RF Blockset 1.0.2 (R14SP1)

This enhancement has been incorporated in Release 14 Service Pack 3 (R14SP3). For previous product releases, read below for any possible workarounds:

In the attached model, by placing a filter after the output port (IF port) of the mixer, you can see that the RF Blockset has "tagged" the complex baseband representation as being centered at the IF frequency (300 MHz, in this case).

Although the block is called General Mixer, it actually models both a mixer and its corresponding local oscillator (LO).

MATLAB: MEX – ‘Initialization From Incompatible Pointer Type’ Warning

Rowan - rather than using a bool perhaps you could try to use a mxLogical instead? Something like

plhs[0] = mxCreateLogicalMatrix(n_rows, n_cols);  // Create output matrix
mxLogical *output_ptr = mxGetLogicals(plhs[0]);
for (int i = 0; i < n_cols; i++)
{
    output_ptr[i] = (mxLogical)element_even(input_arr[i]);
}

I haven't tested the above and am not sure of the cast to mxLogical but i think that is what you might want to try to do (the cast would be unnecessary if the element_even function returns a mxLogical instead of a bool.

As for the warning, the documentation for mxLogical mentions how All logical mxArrays store their data elements as mxLogical rather than as bool. So the warning message does make sense (a cast to a bool may remove that warning but I think using mxLogical might be the preferred approach).

Best Answer

Related Solutions

MATLAB: Where can I find more information about the implementation of the General Mixer block in RF Blockset 1.0.2 (R14SP1)

MATLAB: MEX – ‘Initialization From Incompatible Pointer Type’ Warning

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