- 26 -
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