NXC - command execution times

[floydbloke]

Using NXC, I’m trying to get a better grasp on when commands are executed.

Let’s say I’ve got the following the code:

Code: Select all

RotateMotor(OUT_A, 30, 360);
RotateMotor(OUT_B, 40, 180);

Am I right in thinking that pretty well straight after Motor A starts turning, Motor B will start turning as well, i.e. it won’t wait for Motor A to finish.

If the above is correct, what would happen if:

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RotateMotor(OUT_A, 30, 360);
Off(OUT_A);

Would Motor A not complete its 360 degree turn?

What is the best way to ensure that Motor A finishes its turn? I have tried inserting a Wait command after starting Motor A but results seem rather inconsistent.
Would this work?

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while(MotorRunState(OUT_A)!= OUT_RUNSTATE_IDLE)
  {
  }

To ensure that A finishes prior to starting B

[afanofosc]

The RotateMotor command is an API function that does not return until the motor(s) complete their specified rotation. So if you want both A and B to turn simultaneously you will need to use multiple threads. If you want motor B to start rotating after A stops then simply put the two commands back to back as you show in your first code block.

John Hansen

[floydbloke]

The RotateMotor command is an API function that does not return until the motor(s) complete their specified rotation. So if you want both A and B to turn simultaneously you will need to use multiple threads. If you want motor B to start rotating after A stops then simply put the two commands back to back as you show in your first code block.

John Hansen

Thanks John, that answers the question.
I though I had observed the motors turning simultaneously but am obviously mistaken, or have errors in my code elsewhere.