Spec_ComponentBase.md

Specification of Component class

1. Overview

1. Functions

• The Component class is an abstract class to handle the electrical power and the update timing of components.
• This class has two virtual functions: MainRoutine and FastUpdate. Both are called periodically. Users can select the functions according to the required calling period.
  • The MainRoutine function is the components' main function. Most of the processing is handled in this function.
  • The FastUpdate function handles the processes that need to be computed in a high-speed cycle. So, users will use this function only when high-frequency disturbances need to be calculated (e.g., RW jitter).

2. Related Files

• Main file: component.hpp, component.cpp

3. How to use

• Inherit this class by the user's component class.
• The ReactionWheel in S2E_CORE is useful as a usage example of the FastUpdate.

2. Explanation of Algorithm

1. Constructor

1. overview

• Users can set component update prescaler and power port.

2. inputs

• prescaler
  • prescaler determines the execution cycle of the MainRoutine function.
  • The period of MainRoutine equals to SimTime::compo_update_interval_sec $\times$ prescaler.
• clock_gen
  • clock_gen is an instance that simulates the clock of a component.
  • Users do not need to care about this.
• power_port
  • power_port is an instance that simulates the power supply
• fast_prescaler
  • fast_prescaler determines the execution cycle of the FastUpdate function.
  • The period of FastUpdate equals to SimTime::compo_update_interval_sec $\times$ fast_prescaler.
  • If you don't need to use FastUpdate, you don't need to specify this (it is set to 1 by default).

3. algorithm

• N/A

4. note

• N/A

2. MainRoutine

1. overview

• Components' main function

2. inputs

• time_count
  • time_count is incremented each time the Tick function is called.
  • Users can use this timing information when they need for their components.

3. algorithm

• N/A

4. note

• All the components have to override the MainRoutine function.

3. FastUpdate

1. overview

• This function handles the processes that need to be computed in a high-speed cycle.

2. inputs

• N/A

3. algorithm

• N/A

4. note

• FastUpdate function is not a pure virtual function, so components without fast calculation do not need to override this function.
• As explained in the FastTick section, ITickable::needs_fast_update_ flag must be true to call FastUpdate. So, if users want to use FastUpdate, call ITickable::SetNeedsFastUpdate(true) in the constructor of each component.

4. Tick

1. overview

• This function executes MainRoutine.
• ClockGenerator class calls this function.

2. inputs

• count
  • count is incremented each time the Tick function is called.

3. algorithm

• Execute MainRoutine when the count is divisible by the prescaler. By this mechanism, the execution period of MainRoutine is divided.

4. note

• N/A

5. FastTick

1. overview

• This function executes FastUpdate.
• ClockGenerator class calls this function.

2. inputs

• count
  • count is incremented each time the FastTick function is called.

3. algorithm

• Execute FastUpdate when the count is divisible by the fast_prescaler. By this mechanism, the execution period of FastUpdate is divided.

4. note

• ITickable::needs_fast_update_ flag must be true to call FastUpdate. So, if you want to use FastUpdate, call ITickable::SetNeedsFastUpdate(true) in the constructor of each component.

3. Results of verifications

• N/A

4. References

• N/A