Devices, model definitions, commands, and subcircuit definitions are all stored in a linked list, and are defined by classes derived from “CARD”. The container is a CARD_LIST.
Device instances are derived from COMPONENT, which is derived from CARD.
Model and paramset statements are derived from MODEL_CARD, which is derived from CARD.
There are special classes of devices that are derived from COMPONENT.
| COMPONENT | e_compon.h | all devices, including those defined by subcircuit expansion. |
| BASE_SUBCKT | e_subckt.h | devices that are defined in terms of other devices, as subcircuits, with an internal hierarchy. |
| ELEMENT | e_elemnt.h | devices that are not defined in terms of other devices. |
| STORAGE | e_storag.h | elements that store some historical information, such as previous states. |
Devices do not contain any parsing or printing code, but do contain methods for setting and reading parameters.
Some devices do contain parsing or printing code in methods with a name that includes “obsolete_callback”. That is not documented here, and will eventually be removed.
One static object of every type is created at program startup or when a plugin is loaded. A pointer to that static object is installed in a dispatcher, and later accessed by name or through that pointer. This is the only interface.
Device plugins need to include at least one file, defining its base class. Often, that is the only include file needed.