Model Composer provides a configuration wizard that makes it easy to associate a VHDL or Verilog module to a Black Box block. The Configuration Wizard parses the VHDL or Verilog module that you are trying to import, and automatically constructs a configuration M-function based on its findings. Then, it associates the configuration M-function it produces to the Black Box block in your model. Whether or not you can use the configuration M-function as is depends on the complexity of the HDL you are importing. Sometimes the configuration M-function must be customized by hand to specify details the configuration wizard misses. Details on the construction of the configuration M-function can be found in the Black Box Configuration M-Function topic.