Renesas 70 - Manual (Page 29)

Chapter 3 Introduction to MR308
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3.3 Task
This section describes how tasks are managed by MR308.
3.3.1 Task Status
The real-time OS monitors the task status to determine whether or not to execute the tasks.
Figure 3.12 shows the relationship between key input task execution control and task status. When there is a
key input, the key input task must be executed. That is, the key input task is placed in the execution (RUNNING)
state. While the system waits for key input, task execution is not needed. In that situation, the key input task in
the WAITING state.
Key input
Task
RUNNIG state WAITING state RUNNING state
Waiting for
key input
Key input
processing
Key input
processing
Figure 3.12 Task Status
The MR308 controls the following six different states including the RUNNING and WAITING states.
1. RUNNING state
2. READY state
3. WAITING state
4. SUSPENDED state
5. WAITING-SUSPENDED state
6. DORMANT state
Every task is in one of the above six different states. Figure 3.13 shows task status transition.