help with coding for a stepper motor

Other Hardware Motors, Mechanics, Power and CNC
12

I can't say I can follow the logic of your code but these two things come to mind

These two lines make no sense because the only one that will be recognized is the second one

      stepper.moveTo(100);
      stepper.moveTo(-100);

And this line

  if (digitalRead(pirPin) == LOW)

uses a completely different value from the pirPin to the value in the first IF statement. It is entirely possible that both IF statements could be true.

Try changing the line I have quoted to this

else

so that that part of the code is called if the first reading of pirPin is LOW

Can you explain the purpose of your different boolean variables?

...R