Two functions at same time

VEX V5 General Discussion General Forum
#1

Hi everyone, I recently came into a problem when trying to code a stacking macro. I had previously made a task to let me drive my robot while it performed a towering macro, which went like this…

int myTaskCallback() {
int count = 0;
while (true) {
driveLeft.spin(vex::directionType::fwd, Controller1.Axis3.position(),vex::velocityUnits::pct);
driveRight.spin(vex::directionType::rev, Controller1.Axis2.position(),vex::velocityUnits::pct);
count++;
}
return 0;
}

it ended up working… however, after this I noticed that I could not drive back in my stacking macro for some reason not related to the build of the robot. I tried messing with thread callbacks, but nothing worked. Does anyone know how to fix this?

#2

You can actually use threads, but it is best to run threads as long-lived loops, not short lived functions.

For example, you could have:

void DriveThread() {
  while(true) {
    //Drive code
    vex::task::sleep(20);
  }
}

void IntakeThread() {
  while(true) {
    //Intake code
    vex::task::sleep(20);
  }
}

void Opcontrol() {
  vex::thread t_Drive(DriveThread);
  vex::thread t_Intake(IntakeThread);

  //while loop so it dont exit
  while(true) vex::task::sleep(20);
}

Edit: at the suggestion of @Mercerbots, I added sleep statements to make it more clear that you need to have sleep statements or the code will hang.

2 Likes
#3

I would need to see more code to see if there are other issues but it’s worth noting that you do not have a pause in your while loop. The pause is necessary to allow the CPU to allocate time to other threads. As it is now, unless the compiler is smart enough to optimize it for you, the above thread will run continuously.