While Loop

Programming Support VEX Coding Studio Tech Support
4

And, in case if you are looking for even more nitty-gritty technical details …

VexOS uses cooperative scheduler, which means that, unless one tasks yields the CPU, other tasks couldn’t run.

In the first, non-competition example, main() task starts sensorMonitoringTask(). However, VexOS will let it run only when the main loop makes a system call that yields the CPU, like vex::task::sleep(). If main task never calls such function the second task will never get to run and vice versa.

int sensorMonitoringTask()
{
   while(1) { // loop forever
    // do something useful ...
    vex::task::sleep( 10 );
   }
}

int main()
{
    vex::task task1(sensorMonitoringTask); // this will start task

    while(1) // main user interface loop
    {
      if( button1.pressing() )
      {
         // display something, run some motors, ...
      }
      vex::task::sleep(10); // yield time to other tasks
    }
}

For VRC robots, when you want them to obey competition switch, that controllers must be plugged into during the matches, you will need to follow special template:

vex::competition Competition; // https://help.vexcodingstudio.com/#cpp/namespacevex/classvex_1_1competition/autonomous

// Autonomous Task - This task is used to control your robot during the autonomous phase of a VEX Competition.
void autonomous( void )  {
    // run robot forward for 3 seconds and kick the ball
}

//  User Control Task - This task is used to control your robot during the user control phase of a VEX Competition. 
void usercontrol( void ) {
  while (1){ // main loop
   // check for user input
   // run some motors
   vex::task::sleep(10); // yield time to other tasks
  }
}

int main() { // Program gets control here
  // if necessary run the pre-autonomous functions, like starting sensorMonitoringTask(), 
  
  //Set up callbacks for autonomous and driver control periods.
  Competition.autonomous( autonomous );
  Competition.drivercontrol( usercontrol );

  //Prevent main from exiting with an infinite loop.                         
  while(1) { // this essentially does nothing, but yields time to other tasks. 
     vex::task::sleep(100);//Sleep the task for a short amount of time to prevent wasted resources.
  }    
}
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