Renesas 70 Manual De Usuario

   

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The MR308 kernel modules are outlined below. 

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Forms a task processing queue based on task priority and controls operation so that the high-priority 

task at the beginning in that queue (task with small priority value) is executed. 

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Exercises the management of various task states such as the RUNNING, READY, WAIT, and SUS-

PENDED state. 

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Accomplishes inter-task synchronization by changing the task status from a different task. 

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Makes a return from the interrupt handler. 

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Sets up the system timer used by the MR308 kernel and starts the user-created alarm handler

cyclic handler.

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Gets the system status of MR308. 

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Reports the MR308 kernel version number or other information. 

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This is the function for synchronization and communication among the tasks. The following three func-

tional modules are offered. 
♦ Eventflag 

Checks whether the flag controlled within the MR308 is set up and then determines whether or not 

to initiate task execution. This results in accomplishing synchronization between tasks. 

♦ Semaphore 

Reads the semaphore counter value controlled within the MR308 and then determines whether or 

not to initiate task execution. This also results in accomplishing synchronization between tasks. 

♦ Mailbox 

Provides inter-task data communication by delivering the first data address. 

♦ Data 

queue 

Performs 32-bit data communication between tasks. 

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Provides dynamic allocation or release of a memory area used by a task or a handler. 

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Outside the scope of µITRON 4.0 Specification , this function performs reset processing on short data 

queues and objects. 

                                                      

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  This handler actuates once only at preselected times. 

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  This handler periodically actuates.