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Version 2.4 (R2009a) Filter Design HDL Coder Software

This table summarizes what's new in Version 2.4 (R2009a).

New Features and Changes	Version Compatibility Considerations	Fixed Bugs and Known Problems	Related Documentation at Web Site
Yes Details below	Yes—Details labeled as Compatibility Considerations, below. See also Summary.	No	No

New features and changes introduced in this version are:

• Complex Data Type Support for FIR, CIC, and Other Filter Structures

• Generation of Simulink Model for Cosimulation of Generated HDL Code

• Support for Programmable Coefficients for FIR Filters with Serial Architectures

• Support for Programmable Coefficients for IIR Filters

• Default Entity Conflict Postfix Changed

Complex Data Type Support for FIR, CIC, and Other Filter Structures

The coder now supports use of complex coefficients and complex input signals for fully parallel FIR, CIC, and some other filter structures. In many cases, you can use complex data and complex coefficients in combination. The following table shows the filter structures that support complex data and/or coefficients, and the permitted combinations.

Filter Structure	Complex Data	Complex Coefficients	Complex Data and Coefficients
dfilt.dffir	Y	Y	Y
dfilt.dfsymfir	Y	Y	Y
dfilt.dfasymfir	Y	Y	Y
dfilt.dffirt	Y	Y	Y
dfilt.scalar	Y	Y	Y
dfilt.delay	Y	N/A	N/A
mfilt.cicdecim	Y	N/A	N/A
mfilt.cicinterp	Y	N/A	N/A
mfilt.firdecim	Y	Y	N
mfilt.firinterp	Y	Y	N
mfilt.linearinterp	Y	N/A	N/A

Properties Supporting Complex Data Types

The new InputComplex code generation property instructs the coder whether or not to generate the appropriate ports and signal paths for the real and imaginary components of a complex signal. To enable generation of ports for complex input data, set InputComplex 'on', as in the following code example:

Hd = design(fdesign.lowpass,'equiripple','Filterstructure','dffir');
generatehdl(Hd, 'InputComplex', 'on');

Two new code generation properties have been added to help you customize naming conventions for the real and imaginary components of complex signals in generated HDL code. The new properties are:

• The ComplexRealPostfix property specifies a string to be appended to the names generated for the real part of complex signals. The default postfix is '_re'. See also ComplexRealPostfix.

• The ComplexImagPostfix property specifies a string to be appended to the names generated for the imaginary part of complex signals. The default postfix is '_im'. See also ComplexImagPostfix.

See Using Complex Data and Coefficients in the Filter Design HDL Coder User's Guide for complete details on complex data type support.

Generation of Simulink Model for Cosimulation of Generated HDL Code

The coder supports generation of a Simulink model that is configured for:

• Simulink simulation of your filter design

• Cosimulation of your design with an HDL simulator

The generated model includes a behavioral model of the filter design, realized in a Simulink subsystem, and a corresponding HDL Cosimulation block, configured to cosimulate the filter design using Simulink. You can generate an HDL Cosimulation block for either of the following EDA Simulator Link™ products:

• EDA Simulator Link (default)

• EDA Simulator Link

See Generating a Simulink Model for Cosimulation with an HDL Simulator for further information.

Support for Programmable Coefficients for FIR Filters with Serial Architectures

For FIR filters with serial architectures, the coder now supports generation of a memory interface for loading coefficients, and generation of testbench coefficients to test the interface. In previous releases, these options were supported only for fully parallel FIR filters.

Programmable coefficients are supported for all serial architecture options (fully serial, partly serial, and cascade serial) of the following direct-form FIR filter types:

• dfilt.dffir

• dfilt.dfsymfir

• dfilt.dfasymfir

For detailed information, see Specifying Programmable Filter Coefficients for FIR Filters in the Filter Design HDL Coder User's Guide.

Support for Programmable Coefficients for IIR Filters

For IIR filters, the coder now supports generation of a memory interface for loading coefficients, and generation of testbench coefficients to test the interface. In previous releases, this option was supported only for FIR filters.

The following IIR filter types support programmable filter coefficients:

• Second-order section (SOS) infinite impulse response (IIR) Direct Form I (dfilt.df1sos )

• SOS IIR Direct Form I transposed (dfilt.df1tsos)

• SOS IIR Direct Form II (dfilt.df2sos)

• SOS IIR Direct Form II transposed (dfilt.df2tsos)

For detailed information, see Specifying Programmable Filter Coefficients for IIR Filters in the Filter Design HDL Coder documentation.

Default Entity Conflict Postfix Changed

The default value for the Entity conflict postfix property (and the corresponding CLI property, EntityConflictPostfix) has been changed from '_entity' to '_block'.

Compatibility Considerations

If your scripts rely on the previous default value ('_entity') for the Entity conflict postfix property, you will need to explicitly set the property value to '_entity'.

Version 2.5 (R2009b) Filter Design HDL Coder Software

Version 2.3 (R2008b) Filter Design HDL Coder Software

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