PikaStdTask multitasking

The PikaStdTask multitasking library provides asynchronous multitasking capabilities of Task (task loop).

class Task():

The Task class provides the task loop function, and a task loop can be created by creating an object of the Task class.

Methods of the Task class

import PikaStdData


class Task:
    calls = PikaStdData.List()

    def __init__(self):
        pass

    # regist a function to be called always
    def call_always(self, fun_todo: any):
        pass
    
    # regist a function to be called when fun_when() return 'True'
    def call_when(self, fun_todo: any, fun_when: any):
        pass

    # register a function to be called periodically
    def call_period_ms(self, fun_todo: any, period_ms: int):
        pass

    # run all registered function once
    def run_once(self):
        pass

    # run all registered function forever
    def run_forever(self):
        pass

    # run all registered function until time is up
    def run_until_ms(self, until_ms: int):
        pass

    # need be overried to supply the system tick
    def platformGetTick(self):
        pass

Instructions:

Use the call_xxx() method to specify the calling method, and register the function to be executed in the task object.

Use the run_xxx() methods to specify how the task loops and execute all functions in the task object.

Time-related functions, such as call_period_ms() and run_until_ms(), need to provide the system clock by creating a new class that inherits from PikaStdTask, and then override the platformGetTick() method.

Notice:

All registered functions should be non-blocking, otherwise the entire task loop will be blocked.

The task loop is not real-time.

Example:

Create a new class that inherits from PikaStdTask.

# STM32G0.py
class Task(PikaStdTask.Task):
    # override
    def platformGetTick():
        pass

Override the platformGetTick() method.

/* STM32G0_Task.c */

void STM32G0_Task_platformGetTick(PikaObj* self) {
    obj_setInt(self, "tick", HAL_GetTick());
}

Python use cases