Task processor

摘要

A task processor includes a CPU, a save circuit, and a task control circuit. A task control circuit is provided with a task selection circuit and state storage units associated with respective tasks. When executing a predetermined system call instruction, the CPU notifies the task control circuit accordingly. When informed of the execution of a system call instruction, the task control circuit selects a task to be subsequently executed in accordance with an output from the selection circuit. When an interrupt circuit receives a high-speed interrupt request signal, the task switching circuit controls the state transition of a task by executing an interrupt handling instruction designated by the interrupt circuit.

主权项

1. A task control circuit connected via a signal line to a processor which executes a task, comprising:
a state register that stores state data representing state of a task; and a task switching circuit that controls state of a task, wherein the task switching circuit, when a system call signal is received from the processor, reads out a parameter from an internal register of the processor by itself, performs a system call process based on the parameter, updates the state data, and writes back a return value resulting from the system call process in the internal register by itself.