Ramping Down the variable in Arduino IDE with the help of millis()??......

by the way, what I could use to tell the same setpoint variable in the program above, to stay at one value for 1 second and then ramp down to zero again?. As I know the delay(time) function HALTS the program at that point, which means that it will not work. Are there other ways to tell variables to stay at certain value for a certain time?

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