Increment and decrement with a Boolean input

Hello Labview Experts (and life savers actually !!)
In my VI ,I have a numerical controller (knob) feeding a numerical indicator ,in addition to a bolean input.
As an initial state the numerical indicator will contain a certain value (zero for example) and will only receive the variation in the knob input as long as the bolean input is true and then add it to this initial value.
what is the variation ? lets say that the knob was on 8 before i hit the boolean true ,the indicator's value is zero ,and then I hit the boolean true ,
Now ,when i move the knob from 8 to 18 (+10 variation) ,I want the indicator to receive +10 and add it to the zero ,now the result is 0+10=10.
Now the boolean is false ,I move the knob and nothing happens to the 10 in the indicator.
Now the boolean is true again ,let's to say the knob was on 4 at the time i hit the boolean true ,and I move it from 4 to 1 (-3 variation) ,the indicator's value now will be 10+ (-3) = 7
I hope I explained the idea in a clear way ,I would be very thankful if someone would help me with that.
P.S. I only attached the vi for illustrating the idea.
Thanks in advance
Solved!
Go to Solution.
Attachments:
main components.vi ‏7 KB

You only care about how much the knob changed. Therefore, you need to subtract the old value and the new value to get how much the knob changed. Then inside the case structure, add that difference to your value that belongs in the shift register.
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Attachments:
Incremental_BD.png ‏7 KB

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