Creating bottom-up design

Bottom-up design can be created by using clipboard functions at the design hierarchy explorer. After designing lower-level modules, the modules can be used at higher design hierarchy seamlessly. This is done by adding the higher hierarchy module at the design hierarchy explorer, then cut those lower level modules and paste them under the higher hierarchy module.

In this tutorial, a one-digit counter with 7-segment display output is demonstrated. Select the top item at the design hierarchy explorer, then add a new module with the name "digit". Select the Hex2LED module and invoke Edit -- Cut (Ctrl+X). Select the digit module and invoke Edit -- Paste (Ctrl+V). The Hex2LED module is now placed under the digit module. Analyze the digit module and open the VHDL file, it can be seen that the component declaration and a sample component instantiation of the Hex2LED module are added in the VHDL code.