6.9.1. Performing a Cosimulation
The design example has two HDL entities: the DPD (lut_dpd.vhd) and the FIR (complex_fir.vhd).
In DSP Builder cosimulation, each HDL Import block represents an HDL instance. You must instantiate both of these entities in a top-level VHDL file. For this design example, Intel provides top.vhd.
In addition, the FIR filter uses a signed data type with a generic for the data width. When DSP Builder instantiates the FIR filter, it uses its own paradigm (i.e. std_logic_vector and no generics). This design example adds a wrapper entity: complex_fir_wrapper.vhd. This entity instantiates complex_fir, including setting the generic to the appropriate value, and converts signed to std_logic_vector.
These two files, top.vhd and complex_fir_wrapper.vhd are in the to_import directory.
Procedure
-  Add a HDL Import Config block to the top-level design. 
    Figure 74. Top-level Design with HDL Import Config Block  
-  Parameterize the HDL Import Config block. 
    -  Click Add to add all of the files from the to_import directory.  
      The order of the files does not matter. DSP Builder determines the type of HDL file by the extension, but you can change the type manually.
- Enter top in the Top level instance.
- Turn on Top-level is a wrapper.
- Click the Compile button.
- Set the Simulink sample time field to 1.
- When the status light is green, click Launch Cosim.
 Figure 75. HDL Import Configuration  
-  Click Add to add all of the files from the to_import directory.  
      
-  Add a HDL Import block to the digital_up_converter subsystem. 
    - Double click the HDL Import block
- Click Instance and select inst_fir.
-  Set the fractional bits of the two output signals to 16. 
      Figure 76. HDL Import Block inst_fir Parameters  
 
-  Add a second HDL Import block to the digital_up_converter subsystem. 
    - Double click the HDL Import block
- Click Instance and select inst_dpd.
- Set the fractional bits of the two output signals to 27.
- Set the valid output to unsigned.
 Figure 77. HDL Import inst_dpd Parameters  
-  Wire up HDL import blocks. 
    The HDL Import block port names are in alphabetical order.Figure 78. Wire up HDL Import Blocks  
- Press the play button or advance through the simulation a cycle at a time.
-  Verify HDL import with the ModelSim simulator, in DSP Builder, select DSP Builder > Run ModelSim > Device. 
    The cosimulation turns any non-high state (e.g. U or X) to a zero.
- Compile the design in Quartus® Prime, by selecting DSP Builder > Run Quartus Prime Software.