| ################################## |
| Welcome to cocotb's documentation! |
| ################################## |
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| .. |
| This documentation tries to follow https://www.divio.com/blog/documentation/ (Daniele Procida) |
| Other media about the same topic: |
| - https://ep2018.europython.eu/media/conference/slides/get-your-documentation-right.pdf |
| - https://www.youtube.com/watch?v=t4vKPhjcMZg |
| - A good example: http://docs.django-cms.org/en/latest/contributing/documentation.html#contributing-documentation |
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| See also https://github.com/cocotb/cocotb/wiki/Howto:-Writing-Documentation |
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| *************** |
| What is cocotb? |
| *************** |
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| **cocotb** is a *COroutine* based *COsimulation* *TestBench* environment for verifying VHDL and SystemVerilog :term:`RTL` using `Python <https://www.python.org>`_. |
| |
| cocotb is completely free, open source (under the `BSD License <https://en.wikipedia.org/wiki/BSD_licenses#3-clause_license_(%22BSD_License_2.0%22,_%22Revised_BSD_License%22,_%22New_BSD_License%22,_or_%22Modified_BSD_License%22)>`_) and hosted on `GitHub <https://github.com/cocotb/cocotb>`_. |
| |
| cocotb requires a simulator to simulate the :term:`HDL` design |
| and has been used with a variety of simulators on Linux, Windows and macOS. |
| Please check the :ref:`simulator-support` page for specifics. |
| |
| A (possibly older) version of cocotb can be used live in a web browser on `EDA Playground <https://www.edaplayground.com>`_. |
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| ************************ |
| How is cocotb different? |
| ************************ |
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| cocotb encourages the same philosophy of design re-use and randomized testing as |
| `UVM <https://en.wikipedia.org/wiki/Universal_Verification_Methodology>`_, |
| however is implemented in Python. |
| |
| With cocotb, VHDL or SystemVerilog are normally only used for the design itself, not the testbench. |
| |
| cocotb has built-in support for integrating with continuous integration systems, |
| such as Jenkins, GitLab, etc. through standardized, machine-readable test reporting formats. |
| |
| cocotb was specifically designed to lower the overhead of creating a test. |
| |
| cocotb automatically discovers tests so that no additional step is required to add a test to a regression. |
| |
| All verification is done using Python which has various advantages over using SystemVerilog or VHDL for verification: |
| |
| * Writing Python is **fast** - it's a very productive language. |
| * It's **easy** to interface to other languages from Python. |
| * Python has a huge library of existing code to **re-use**. |
| * Python is **interpreted** - tests can be edited and re-run without having to recompile the design. |
| * Python is **popular** - far more engineers know Python than SystemVerilog or VHDL. |
| |
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| ********************* |
| How does cocotb work? |
| ********************* |
| |
| A typical cocotb testbench requires no additional :term:`RTL` code. |
| The Design Under Test (:term:`DUT`) is instantiated as the toplevel in the simulator without any wrapper code. |
| cocotb drives stimulus onto the inputs to the :term:`DUT` (or further down the hierarchy) and monitors the outputs directly from Python. |
| Note that cocotb can not instantiate :term:`HDL` blocks - your DUT must be complete. |
| |
| .. image:: diagrams/svg/cocotb_overview.svg |
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| A test is simply a Python function. |
| At any given time either the simulator is advancing time or the Python code is executing. |
| The :keyword:`await` keyword is used to indicate when to pass control of execution back to the simulator. |
| A test can spawn multiple coroutines, allowing for independent flows of execution. |
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| .. toctree:: |
| :maxdepth: 1 |
| :hidden: |
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| quickstart |
| install |
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|
| .. |
| Tutorials - lessons that take the reader by the hand through a series of steps to complete a project |
| (Example: kid cooking; learning-oriented) |
|
|
| - learning by doing |
| - getting started |
| - inspiring confidence |
| - repeatability |
| - immediate sense of achievement |
| - concreteness, not abstraction |
| - minimum necessary explanation |
| - no distractions |
|
|
| .. toctree:: |
| :maxdepth: 1 |
| :caption: Tutorials |
| :name: tutorials |
| :hidden: |
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| examples |
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|
| .. |
| How-To Guides - guides that take the reader through the steps required to solve a common problem |
| (Example: recipe; problem-oriented) |
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|
| - a series of steps |
| - a focus on the goal |
| - addressing a specific question |
| - no unnecessary explanation |
| - a little flexibility |
| - practical usability |
| - good naming |
|
|
| .. toctree:: |
| :maxdepth: 1 |
| :caption: How-to Guides |
| :name: howto_guides |
| :hidden: |
| |
| writing_testbenches |
| runner |
| coroutines |
| triggers |
| custom_flows |
| rotating_logger |
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|
| .. todo:: |
| - Add IPython section |
| - How to deal with existing Verification IP? |
| - Point to https://github.com/cocotb/cocotb/wiki/Code-Examples |
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|
|
| .. |
| Explanation (Background, Discussions) - discussions that clarify and illuminate a particular topic |
| (Example: history of cooking; understanding-oriented) |
|
|
| - giving context |
| - explaining why |
| - multiple examples, alternative approaches |
| - making connections |
| - no instruction or technical description |
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| .. toctree:: |
| :maxdepth: 1 |
| :caption: Key topics |
| :name: key_topics |
| :hidden: |
| |
| install_devel |
| troubleshooting |
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|
| .. todo:: |
| - Move section "How does cocotb work?" from Introduction to here |
| - Add some info from :doc:`coroutines` |
| - Add GPI section |
| - Explain ``ReadOnly``, ``ReadWrite``, ... phases |
| - Add pitfall from https://github.com/cocotb/cocotb/issues/526#issuecomment-300371629 to troubleshooting |
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|
| .. |
| Reference - technical descriptions of the machinery and its operation |
| (Example: Wikipedia pages of ingredients; information-oriented) |
|
|
| - structure |
| - consistency |
| - description |
| - accuracy |
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| .. toctree:: |
| :maxdepth: 1 |
| :caption: Reference |
| :name: reference |
| :hidden: |
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| building |
| Python Code Library Reference <library_reference> |
| GPI Library Reference <library_reference_c> |
| simulator_support |
| platform_support |
| extensions |
| refcard |
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| .. toctree:: |
| :maxdepth: 1 |
| :caption: Development & Community |
| :name: development_community |
| :hidden: |
| |
| roadmap |
| contributors |
| release_notes |
| further_resources |
| |
| .. todo:: |
| - Add "Join us online" and "Contributing" |
| - In Contributing, add explanation on how to provide a PR, how to test existing PRs, etc. |
| - merge `further_resources` into Contributing |
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| .. toctree:: |
| :maxdepth: 1 |
| :caption: Index |
| :name: index |
| :hidden: |
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| Classes, Methods, Variables etc. <genindex> |
| Python Modules <py-modindex> |
| glossary |
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