SNIP_CLASSIC_OS_SECTION_7_3_2_5_Controlling_ScheduleTable_Processing

7.3.2.5 Controlling ScheduleTable Processing The application is responsible for starting and stopping the processing of a Schedule Table. The Operating System module provides the service StartScheduleTableAbs (see [SWS_Os_00358]) to start the processing of a ScheduleTable at an absolute value "Start" on the underlying Counter. (The Initial Expiry Point has to be processed when the value of the underlying Counter equals Start + InitialOffset). The Operating System module provides the service StartScheduleTableRel (see [SWS_Os_00347]) to start the processing of a ScheduleTable at "Offset" relative to the "Now" value on the underlying Counter (The Initial Expiry Point shall be processed when the value of the underlying Counter equals Now + Offset + InitialOffset). The figure below illustrates the two different methods for a ScheduleTable driven by a Counter with a modulus of 65536 (i.e. an OsCounterMaxAllowedValue = 65535). Figure 7.3: Starting a ScheduleTable at an Absolute and a Relative Count The Operating System module provides the service StopScheduleTable (see [SWS_Os_00006]) to cancel the processing of a ScheduleTable immediately at any point while the ScheduleTable is running. [SWS_Os_00428] Upstream requirements: SRS_Os_00098 ⌈If ScheduleTable processing has been cancelled before reaching the Final Expiry Point and is subsequently restarted then [SWS_Os_00358]/[SWS_Os_00347] means that the re-start occurs from the start of the ScheduleTable.⌋ The Operating System module provides the service NextScheduleTable (see [SWS_Os_00191]) to switch the processing from one ScheduleTable to another ScheduleTable. [SWS_Os_00414] Upstream requirements: SRS_Os_00099 ⌈When a ScheduleTable switch is requested, the OS shall continue to process expiry points on the current ScheduleTable. After the Final Expiry Point there will be a delay equivalent to Final Delay ticks before processing the switched-to ScheduleTable. The initial expiry point will be processed after initial offset.⌋ The Operating System module provides the service GetScheduleTableStatus (see [SWS_Os_00227]) to query the state of a ScheduleTable. ScheduleTables can be configured (see chapter 10) to start automatically during start of the Operating System module (like Tasks and Alarms in OSEK OS). OSEK OS defines a specific order: Autostart of Tasks is performed before autostart of alarms. AUTOSAR OS extends this with ScheduleTables. [SWS_Os_00510] Upstream requirements: SRS_Os_00098 ⌈The Operating System module shall perform the autostart of ScheduleTables during startup after the autostart of Tasks and Alarms.⌋