Svc/Interfaces/docs/sdd.md
The Svc interfaces are a set of .fpp files that define FPP interfaces for components to implement. An FPP interface is an FPP file that defines a set of ports. A component that implements an FPP interface must implement handlers for the input ports and has access to the output ports of the interface.
The Svc.Com interface is an interface for implementing the Communications Adapter Interface. Components implementing this interface must follow the Communication Adapter Protocol, which defines when Fw::Success::SUCCESS and Fw::Success::FAILURE may be emitted via comStatusOut. Svc::ComStub implements this interface and uses a ByteStream driver to send and receive data on a TCP/UDP/UART link, and is often used in development and early testing.
The Svc.Deframer interface is an interface for implementing a Deframer component. This interface allows a component to be dropped in the common F´ Uplink stack and implement deframing for a specific communications protocol. The Svc::FprimeDeframer component implements this interface for the F´ communications protocol.
The Svc.Framer interface is an interface for implementing the Framer component. This interface allows a component to be dropped in the common F´ Downlink stack and implement framing for a specific communications protocol. The Svc::FprimeFramer component implements this interface for the F´ communications protocol.
The Svc.Router interface is an interface for implementing a Router component. This interface allows a component to be dropped in the common F´ Uplink stack and implement routing for a project. The Svc::FprimeRouter component implements this interface routing the common F´ packets, as well as passing unknown packets down to another component for further processing.
The Svc.FrameAccumulator interface is an interface for implementing a Frame Accumulator component. This allows a component to be dropped in the common F´ Uplink stack and implement frame accumulation, using any desirable algorithm. The Svc::FrameAccumulator component implements this interface by storing the data in a circular buffer and using a Svc::FrameDetector to detect frames in the buffer.
The Svc.Time interface is an interface for implementing a Time provider. A time provider must provide a way for other components to get the current time. The Svc::PosixTime component implements this interface, using common Posix functions to retrieve the current time.
The Svc.BufferAllocation interface is an interface for components that allocate and deallocate buffers. It provides an allocate output port (Fw.BufferGet) for requesting buffers from a buffer manager and a deallocate output port (Fw.BufferSend) for returning them.