Desired Vs Actual

As the starting point we take the example11 where we have desired and actual value from potentiometers. With LEDs indicate, weather the actual value is below, equal or above desired value.

blue LED ~ too low

green LED ~ actual = desired, i.e. equal

red LED ~ too high

Also provide rectangle on the canvas indicating the state (low, equal, high). At the equal indication, provide a boundary which will stabilise the indication within acceptable error from the desired value.

In the next figures the realised system is shown. When the actual value (green line on the graph) is lower than the desired (red line on the graph), the blue led turns on and on the canvas blue square indicator is shown. Accordingly for the equal and high state (green and red).