MobiFlight Community Support

I have successfully calibrated my C150 vertical speed indicator using the 28BYJ-48 stepper motor , this works great and follows the scale on the instrument up to the maximum which is +/- 2000ft per min.
The problem comes when 2000ftpm is exceeded as the stepper will of course keep moving past 2000, I found a way using the compare tab to limit the movement in the negative direction by setting :
if value is <= -2950
set to -2950
else $

Is there a way to limit both directions of the gauge ?

Any help would be much appreciated !

2 Possible ways.... ( I not try out but this should work)

1. Use Interpolation.

Define a "Overdrive Area" that is verry short on both ends.

Line 1: Input: -10000 = Output -2050
Line 2 Input: -2000 = Ouptut: -2000
Line 3 Input: 0 = Output : 0
Line 4 Input 2000 = Output 2000
Line 5 Input 10000 = Output 2050

Now A Value from -2000 until +2000 is shown 1:1 clearon Gauge.
A Value below -2000 or more then +2000 will change needle only a little bit. ( A Increase by 8000 now means a needle moving like 50 in real)

2. Use a transform
In Compare you can use only one value.... Transformfield is much better for this.
Transform : if($<-2000,-2000,if($>2000,2000,$))

This means.... If Value below -2000 then set -2000 all time.... If Value is bigger then +2000 then set 2000 all time.... If Value is between -2000 and +2000 then show orignal value.

Normaly both should work !

Option 2 worked a treat ! thank you