chipflow.sim.cxxrtl
===================

.. py:module:: chipflow.sim.cxxrtl

.. autoapi-nested-parse::

   CXXRTL C API bindings via ctypes.

   This module provides Python bindings for the CXXRTL simulation engine,
   allowing fast compiled simulation of HDL designs with Python testbenches.



Classes
-------

.. autoapisummary::

   chipflow.sim.cxxrtl.CxxrtlObject
   chipflow.sim.cxxrtl.CxxrtlSimulator


Module Contents
---------------

.. py:class:: CxxrtlObject

   Bases: :py:obj:`ctypes.Structure`


   CXXRTL object descriptor - matches struct cxxrtl_object in cxxrtl_capi.h


.. py:class:: CxxrtlSimulator(library_path, top_module)

   Python wrapper for CXXRTL simulation.

   This class provides a Pythonic interface to CXXRTL compiled simulations,
   supporting signal access, stepping, and VCD tracing.

   Example::

       sim = CxxrtlSimulator("build/design.so", "design")
       sim.reset()

       # Clock cycle
       sim.set("clk", 0)
       sim.step()
       sim.set("clk", 1)
       sim.step()

       # Read output
       value = sim.get("data_out")


   .. py:method:: reset()

      Reset the simulation to initial state.



   .. py:method:: eval()

      Evaluate combinatorial logic.

      :returns: True if the design converged immediately



   .. py:method:: commit()

      Commit sequential state.

      :returns: True if any state changed



   .. py:method:: step()

      Simulate to a fixed point (eval + commit until stable).

      :returns: Number of delta cycles



   .. py:method:: get(name)

      Get the current value of a signal.

      :param name: Signal name (e.g., "i_clk" or "o_data")

      :returns: Current value as an integer



   .. py:method:: set(name, value)

      Set the next value of a signal.

      :param name: Hierarchical signal name
      :param value: Value to set



   .. py:method:: signals()

      Iterate over all signals in the design.

      :Yields: Tuples of (name, object) for each signal



   .. py:method:: inputs()

      Iterate over input signals.



   .. py:method:: outputs()

      Iterate over output signals.



   .. py:method:: close()

      Release simulation resources.