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diff --git a/doc/examples/quick_start/heartbeat/README.rst b/doc/examples/quick_start/heartbeat/README.rst deleted file mode 100644 index e95145095..000000000 --- a/doc/examples/quick_start/heartbeat/README.rst +++ /dev/null @@ -1,42 +0,0 @@ -.. program:: ghdl -.. _QuickStart:heartbeat: - -`Heartbeat` module -================== - -Although :ref:`Hello world <QuickStart:hello>` illustrates that `VHDL` is supported as a general purpose language, the main use case -of `GHDL` is to simulate hardware descriptions. The following block, which is saved in a file named -:file:`heartbeat.vhdl`, is an example of how to generate a 100 MHz clock signal with non-synthesisable VHDL: - -.. literalinclude:: heartbeat.vhdl - :language: vhdl - -It can be :ref:`analysed <Analysis:command>`, :ref:`elaborated <Elaboration:command>` and :ref:`run <Run:command>`, as you already know: - -.. code-block:: shell - - ghdl -a heartbeat.vhdl - ghdl -e heartbeat - ghdl -r heartbeat - -However, execution of the design does not terminate. At the same time, no output is shown on screen. This is because, -traditionally, hardware designs are continuously running devices which do not have a screen where to print. In this -context, inspection and verification of the behaviour is done through `waveforms <https://en.wikipedia.org/wiki/Waveform_viewer>`_, -which is supported by `GHDL` (see :ref:`export_waves`). You can use either :option:`--wave`, :option:`--vcd`, -:option:`--vcdgz` or :option:`--fst` to save the signals of the simulation to a file. Then, terminate the execution -(:kbd:`C-c`) and you can inspect the wave with a viewer, such as `GtkWave <http://gtkwave.sourceforge.net/>`_. As -explained in the `manual <http://gtkwave.sourceforge.net/gtkwave.pdf>`_, GtkWave *'relies on a post-mortem approach -through the use of dumpfiles'*. Therefore, you should first simulate your design and dump a waveform file, say GHW: - -.. code-block:: shell - - ghdl -r heartbeat --wave=wave.ghw - -Then, you can view the dump: - -.. code-block:: shell - - gtkwave wave.ghw - -Of course, manually terminating the simulation is for illustration purposes only. In :ref:`Full adder <QuickStart:adder>` and -:ref:`QuickStart:DLX`, you will see how to write a testbench to terminate the simulation programmatically. |