The :ref:`pdserver` application provides a simulator mode when the --sim argument is provided, which can be used for testing scripts under development. The simulator uses a simple drop model, in which each electrode is either covered or not. A drop located on an inactive electrode, with one or more active electrodes next to it will be moved to one of the active neighbors, and any fluid on a connected drop is pulled along, recursively.
When launching the simulator, a list of pins must be provided. These pins will be initialized with a drop present. For example:
pdserver --board misl_v4.1 --sim 4,5,12 to initialize drops on electrodes 4, 5, and 12.
The simulator is implemented by :py:class:`purpledrop.simulated_purpledrop.SimulatedPurpleDrop`.