Package org.yamcs.time

Class SimulationTimeService

java.lang.Object

org.yamcs.time.SimulationTimeService

All Implemented Interfaces:

TimeService

public class SimulationTimeService
extends Object
implements TimeService

Simulation time model. Can be used by configuring in the yamcs.instance.yaml:

 timeService:
     class: org.yamcs.time.SimulationTimeService
     args:
         time0: 2020-10-02T18:10:00.000Z
         speed: 1.0
 

By default the time0 is initialised with the time at the instance startup and the speed is 1.

The service mantains a simulated time which is running based on the computer clock according to speed (e.g. speed = 2 means it runs two times realtime speed). If the speed is 0, the simulated time never advances and it has to be advanced from other place (see below).

The simulation time service (as well as the speed) can be updated by various means:

• Using the http time API; see https://docs.yamcs.org/yamcs-http-api/time/ for details.
• Setting the option updateSimulationTime: true on a TM Data Link (this is implemented in AbstractTmDataLink) and will cause the simulation time to be updated with the packet generation time each time a packet is received on the corresponding link.
• By a custom service.

Note: using a time0 configured with a fixed value will cause the Yamcs to start always with the same simulation time and that might cause undesired effects such as packets overwriting eachother in the archive.

Such an option is better to be used in a template which can then be used to create always new Yamcs instances (corresponding to test sessions) such that the data is separated. See the instance and templates API .

Constructor Summary

Constructors

Constructor	Description
SimulationTimeService(String yamcsInstance)
SimulationTimeService(String yamcsInstance, YConfiguration config)

Method Summary

Modifier and Type	Method	Description
long	getMissionTime()	The mission time returned is:
void	setSimElapsedTime(long simElapsedTime)
void	setSimSpeed(double simSpeed)	Set the simulation speed.
void	setTime0(long time0)	Set the time0

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.yamcs.time.TimeService

getHresMissionTime

Constructor Detail

SimulationTimeService

public SimulationTimeService(String yamcsInstance,
                             YConfiguration config)

SimulationTimeService

public SimulationTimeService(String yamcsInstance)

Method Detail

getMissionTime

public long getMissionTime()

The mission time returned is:

time0 + simElapsedTime + speed * (System.currentTimeMillis() - javaTime)

where time0 is the value set with setTime0(long), simElapsedTime is the value set with setSimElapsedTime(long) and the javaTime is the value returned by System.currentTimeMillis() last time when setSimElapsedTime(long) has been called.

Specified by:

getMissionTime in interface TimeService

setSimElapsedTime

public void setSimElapsedTime(long simElapsedTime)

setTime0

public void setTime0(long time0)

Set the time0

Parameters:

time0 -

setSimSpeed

public void setSimSpeed(double simSpeed)

Set the simulation speed. If greater than 0, the time passes even without the update of the simElapsedTime.

Parameters:

simSpeed -