Renesas M3T-MR100 Network Card 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