Arduino Multitasking Stackchange Beta 1.1 July 8 2019

CoopOS with Stackframes

You never thought that multitasking can be so easy:

This is a simple and fast approach to multitasking.

• Very easy to use even for beginners - nothing else comes close
• Usable for professionals
• Reliable timings
• Tasks have priorities and own stacks
• Full documentation
• Compatible with all Arduino Libraries
• In the simplified form only one file to include
• Could be combined with RTOS's as Idle-Task
• Easy to port to other processors • Valuable tools for development and tests

• 25000 (40 µs) TaskSwitches per second on Arduino-UNO / -NANO are possible
• Breakpoints in source or with Debug-Button (stop/resume) or serial input
• Breakpoint may show last 20 scheduled tasks with timestamp
• Watchdog-Interrupt to test Task Switching
• Up to 200000 Interrupts/s !

More than 50 pages documentation !

Extract the CoopOS_Stack_MT_Nano.zip file with all features to your Arduino-sketch directory.

But it is highly **recommended** to read the documentation and experiment at first with the Demo files.
This is the simple Demo0 - here we use Cooperative Multitasking with stack-change!

//// CoopOS_Stack_MT - Demo   (C) 2019 Helmut Weber
//// Demo0

#include "TaskSwitchDemo.h"   
#define LED 13

void Task1() {                                    // Blink LED
    while(1) {                                    // <<< You will find these while(1) loops in all RTOS's examples
	digitalWrite(LED,HIGH);                   // if you call this in a normal Arduino sketch nothing else will run !
	Delay(50000);
	digitalWrite(LED,LOW);
	Delay(50000); // microseconds
    }
}


void Task2() {                                    // Write to Serial Line
    while(1) {                                    // Another infinit loop !
	Serial.println("Hello World");
	Delay(1000000);
    }
}

void setup() {
    Serial.begin(500000);
    StackInit();                                  // Init the stacks for all tasks
   
    TaskInit("T1", Task1, 90, 100,   0, READY);   // define 2 tasks for multitasking:
    TaskInit("T2", Task2, 90, 100,   0, READY);
   
    StartMultiTasking();                          // start the system:
}

void loop() {                                     // loop is never called
    //// this is never called !!!
    Serial.println("Hoops? How did you come to this line ???");
}

//// CoopOS_Stack_MT - Demo   (C) 2019 Helmut Weber
//// Demo0
With the final program "TheProgram" it is possible to proof with the WDT

that no task needs more than 100 µs !

That means: highly deterministic !