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3 task priority and waiting queue – Renesas Emulator System M3T-MR100 User Manual

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3.4.3

Task Priority and Waiting Queue

In The standard profiles in µITRON 4.0 Specification support two waiting methods for each object. In one method, tasks
are placed in a waiting queue in order of priority (TA_TPRI attribute); in another, tasks are placed in a waiting queue in
order of FIFO (TA_TFIFO).

Figure 3.18 and Figure 3.19 depict the manner in which tasks are placed in a waiting queue in order of "taskD," "taskC,"
"taskA," and "taskB."

n

Priority

1 Priority

5 Priority

6

taskB

1

ID No.

2

taskA

taskC

taskD

Priority 9

Figure 3.18 Waiting queue of the TA_TPRI attribute

n

Priority

9 Priority

6 Priority

1

taskC

1

ID No.

2

taskD

taskA

taskB

Priority 5

Figure 3.19 Waiting queue of the TA_TFIFO attribute