Core Modules

The core modules provide the most important functionalities of the Flight Software Framework.

Clock

  • This is a class of static functions that can be used at anytime

  • Leap Seconds must be set if any time conversions from UTC to other times is used

Object Manager

  • Must be created during program startup

  • The component which handles all references. All SystemObjects register at this component.

  • All SystemObjects needs to have a unique Object ID. Those can be managed like framework objects.

  • A reference to an object can be retrieved by calling the get function of ObjectManagerIF. The target type must be specified as a template argument. A nullptr check of the returning pointer must be done. This function is based on run-time type information.

    template <typename T> T* ObjectManagerIF::get(object_id_t id);

  • A typical way to create all objects on startup is a handing a static produce function to the ObjectManager on creation. By calling ObjectManager::instance()->initialize(produceFunc) the produce function will be called and all SystemObjects will be initialized afterwards.

Event Manager

  • Component which allows routing of events

  • Other objects can subscribe to specific events, ranges of events or all events of an object.

  • Subscriptions can be done during runtime but should be done during initialization

  • Amounts of allowed subscriptions can be configured in FSFWConfig.h

Health Table

  • A component which holds every health state

  • Provides a thread safe way to access all health states without the need of message exchanges

Stores

  • The message based communication can only exchange a few bytes of information inside the message itself. Therefore, additional information can be exchanged with Stores. With this, only the store address must be exchanged in the message.

  • Internally, the FSFW uses an IPC Store to exchange data between processes. For incoming TCs a TC Store is used. For outgoing TM a TM store is used.

  • All of them should use the Thread Safe Class storagemanager/PoolManager

Tasks

There are two different types of tasks:

  • The PeriodicTask just executes objects that are of type ExecutableObjectIF in the order of the insertion to the Tasks.

  • FixedTimeslotTask executes a list of calls in the order of the given list. This is intended for DeviceHandlers, where polling should be in a defined order. An example can be found in defaultcfg/fsfwconfig/pollingSequence folder