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Min Max Tracker

medium

Track the minimum and maximum of an analog input until a Reset input is pulsed.

What it teaches

Track the highest and lowest values the input has reached. Between resets, each output moves only when a new record is set — Max only rises, Min only falls, otherwise both hold. The trap is Reset: set both outputs to the current input value, not to zero. A Min reset to zero sticks at zero forever, reporting a low that never happened — the first value after a reset is the only honest starting point.

Inputs and outputs

TagTypeDefaultDescription
In_ValueREAL50Analog input value to track
In_ResetBOOLReset signal to re-seed minimum and maximum
Out_MinREALTracked minimum value
Out_MaxREALTracked maximum value

Required behavior

  • On the first scan, Out_Min and Out_Max initialize to the current In_Value to establish a valid baseline.
  • Out_Max updates to match In_Value whenever In_Value is greater than Out_Max.
  • Out_Min updates to match In_Value whenever In_Value is less than Out_Min.
  • Out_Min and Out_Max hold their current values when In_Value is between them.
  • When In_Reset is high, Out_Min and Out_Max are immediately set to the current In_Value.