Wait change block Pro Preview

Now we are going to focus on a well-known block but set differently.

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  • #1073
  • 08 Feb 2019

So far we have programmed the sensors to wait for a condition to evaluate to true – either the value to become smaller or bigger than a given threshold. Today we will program them to wait for a change in the measured value.

What kind of changes can we expect:

  • Touch sensor: That one is easy. The block is waiting for the state of the touch sensor to change either from pressed to released or from released to pressed. 
  • Color sensor: To wait for a change in color. For example, if the sensor measures green, we wait until it starts measuring any other color.

  • For the gyro sensor, the ultrasonic sensor and the color sensor, we wait for the sensor to change the value it is measuring at the moment. Values range from 0 to maximum. 


What does this symbol # stand for?

We program the sensitivity of the block in the number sign, or hashtag symbol as you probably know it. We set how much units exactly the value we receive from the sensor should change in order for the wait block to react.
The units for the various sensors can be expressed in percent, degrees, centimeters, etc.


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