USBB17RX78K4-XXX NEC Electronics, USBB17RX78K4-XXX Datasheet - Page 17

• Manufacturer Part Number: USBB17RX78K4-XXX
• Description: 78K/4 series realtime OS
• Manufacturer: NEC Electronics

2.1 Task State
(1) RUN state
(2) READY state
(3) WAIT state
(4) DORMANT state
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A task can be in any of the following 4 states:
In this state, the task is given the privilege to use the CPU and is under execution. Only one task in the RUN
state can exist in the system at a given point of time.
A task in the state is ready for execution. All the elements to place the task in the RUN state are ready, but the
task in the READY state cannot be executed because a task having the higher priority is currently under
execution.
A task is placed in this state because it has issued a system call to request a resource. A task in this state can
be an event flag waiting for an event, a semaphore waiting for a resource, a mail box waiting for a message, or
waiting for time.
When resetting RX78K/IV, tasks other than the initial one are in a dormant state. When a task is terminated, it
enters the pause state.
CHAPTER 2
BASIC FUNCTIONS OF RX78K/IV