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diff --git a/doc/using/QuickStartGuide.rst b/doc/using/QuickStartGuide.rst index 279969db1..850011fdd 100644 --- a/doc/using/QuickStartGuide.rst +++ b/doc/using/QuickStartGuide.rst @@ -216,3 +216,29 @@ Unless you are only studying VHDL, you will work with larger designs than the on * Remove the :file:`work/` directory: ``rm -rf work``. Only the executable is kept. If you want to rebuild the design, create the :file:`work/` directory, import the sources, and make the design. .. WARNING:: Sometimes, a design does not fully follow the VHDL standards. For example it might use the badly engineered ``std_logic_unsigned`` package. GHDL supports this VHDL dialect through some options: ``--ieee=synopsys -fexplicit``. See section :ref:`IEEE_library_pitfalls`, for more details. + + +Starting with your design +========================= + +Usually your design is more complex than the previous ones. The main +tips are: + +* Don't forget to select the VHDL standard you want to use. The + default is ``--std=93c`` which means VHDL-93 with some relaxed + rules. Use ``--std=08`` for VHDL-2008 (albeit not fully + implemented). All the units must be analyzed with the same standard. + +* Use ``--work=NAME`` to analyze files into the ``NAME`` library. + If you analyze other files from a different directory, give the path + of the ``NAME`` library using ``-P/PATH/TO/NAME/DIRECTORY/``. + +* Use ``--ieee=synopsys`` if your design depends on the non-standard + ieee library. + +* Use ``-fexplicit`` if needed. + +* Use the same options for elaboration. + +So, to analyze a file: ``ghdl -a --std=08 --work=mylib myfile.vhdl`` +To elaborate and run: ``ghdl --elab-run --std=08 top``. |