About AHDL


The Altera Hardware Description Language (AHDL) is a high-level, modular language that is completely integrated into the Quartus II system. You can use the Quartus II Text Editor or another text editor to create AHDL Text Design Files (.tdf). You can then create entire hierarchical projects with AHDL, or mix AHDL TDFs with other types of design files in a hierarchical design. AHDL is especially well suited for designing complex combinational logic, group operations, state machines, truth tables, and parameterized logic.

In the Text Editor, using the Create Symbol Files for Current File command, you can automatically create a Block Symbol File (.bsf) that represents a TDF and incorporate it into a Block Design File (.bdf). Similarly, you can incorporate custom functions and Altera-provided megafunctions and library of parameterized modules (LPM) functions into any TDF. Altera provides AHDL Include Files (.inc) for all megafunctions shipped with the Quartus II software.

Although you can use any ASCII text editor to create AHDL designs, the Quartus II Text Editor allows you to take advantage of features available only in the Quartus II software, including syntax coloring and error location, while you enter, compile, and debug an AHDL design.

You can also check AHDL syntax or perform a full compilation to debug and process your project. You can use the Messages window or the Analysis & Synthesis Messages report to automatically locate any errors and highlight them in the Text Editor window.



Note: All AHDL code must conform to the AHDL syntax established in MAX+PLUS II version 5.0.



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