Svc::ActivePhaser

Svc::ActivePhaser is an active component that drives a set of components connected to Svc::Sched output ports. It periodically schedules port calls by dividing each periodic cycle into ticks and mapping each port call to a window of ticks. Port calls are invoked in the order of their registrations during phaser configuration.

In the example below, a phaser cycle consists of 10 ticks. Port call A (with a length of 2) is set to start at tick 0, port call B (with a length of 3) to start at tick 2, and port call C (with a length of 1) to start at tick 6 & 8. The schedule repeats every 10 ticks.

If a port call is specified a length, this component checks if the call overruns its specified length at runtime.

Requirements

The requirements for Svc::ActivePhaser are as follows:

Requirement	Description	Verification Method
AP-001	The Svc::ActivePhaser component shall be active and will be woken up by an input asynchronous port call	Inspection, Unit test
AP-002	The Svc::ActivePhaser component shall invoke its output ports in the order of port call registrations	Unit Test
AP-003	The Svc::ActivePhaser component shall report a MissedDeadline warning event when a port call overruns its specified length	Unit Test

Design

Component Diagram

The Svc::ActivePhaser component has the following component diagram:

Ports

The Svc::ActivePhaser component uses the following port types:

Port Data Type	Name	Direction	Kind	Usage
Svc::Cycle	CycleIn	Input	Asynchronous	Receive a call to run one cycle of the phaser
Svc::Sched	PhaserMemberOut	Output	n/a	Phaser ports

Port Descriptions

Name	Description
CycleIn	Scheduling input port for executing a phaser cycle
PhaserMemberOut	Output ports for invoking downstream components
timeCaller	Port for requesting current time for telemetry timestamps
logTextOut	Text event port for logging messages
logOut	Event port for binary logs
tlmOut	Port for sending telemetry channels to downlink

Events

Name	Description
MissedDeadline	Emitted when a port call overruns its specified length

Unit Tests

To see unit test coverage run fprime-util check --coverage