Newbie question regarding millis()

[StefanL38]

There is a very important rule you should always follow.
Each time you are posting code. Post the most actual and complete sketch.

Now you left your helpers alone with a single line of code

@biffidum

if (digitalRead(sensewaterstn) == LOW && (currentWaterstn - previousWaterstn5 < DELAY_TIME5)) {

without showing the rest of the code.
Now we - your helpers - have to speculate what the rest of your actual code is

Is it

• the code gcjr has posted?
• the code you have posted in # 24?
• did you change anything else in the code of post # 24?
• is it the code from post # 1?

and this is the reason why you should always each and every time post your complete sketch as a code-section.

scrolling over half a screen is 0,5 seconds.
Asking back or start speculating, sorting together what the rest of the code will be
takes 5 to 50 minutes and requires asking back.

A microcontroller can do 10 case-stages in less than 0,01 seconds
So if everything takes too long it can be corrected in the code if the complete sketch can be seen.

The switch statement is a variation of an if-condition that uses one variable to check a simplified condition

In the example-code this variable has the name "myStateVar"

Depending on the value of variable "myStateVar" only that part of the code that is below this particular value will be executed.
the break statement will cause skipping the other cases.

I add to your your description

@biffidum

• conveyor runs
• bucket breaks light beam
• conveyor stops
• water dispenses for 5 sec
• conveyor starts again

a start button

check if start-button is pressed

• wait for pressing startbutton
• conveyor runs
• bucket breaks light beam
• conveyor stops
• water dispenses for 5 sec
• conveyor starts again

Now a state machine has similarities to a machine that has different modes of operation

mode "wait for pressing startbutton"
mode "conveyor runs"
mode "water dispenses for 5 sec"

to make it easier to see the pattern = for didactical reasons I created some more modes

mode "waitForPressingStart"
mode "moveConveyor"
mode "checkForBucketInPosition"
mode "openWaterValve"
mode "wait5Seconds"
mode "closeWaterValve"

and here is the sketchy sketch that is not yet compilable but shows the principle

const byte waitForPressingStart     = 0;
const byte moveConveyor             = 1;
const byte checkForBucketInPosition = 2;
const byte openWaterValve           = 3;
const byte wait5Seconds             = 4;
const byte closeWaterValve          = 5;


state = waitForPressingStart;

switch (myStateVar) 

  case waitForPressingStart: // only in case myStateVar == waitForPressingStart

    if (digitalRead(startButtonPin == pressed) {
      myStateVar = moveConveyor;
	}
	break; // skip other cases and IMMIDIATELY jump down to END-OF-SWITCH
	

	
  case moveConveyor: // only in case myStateVar == moveConveyor

    digitalWrite(drive, HIGH); 
      myStateVar = checkForBucketInPosition;
	}
	break; // skip other cases and IMMIDIATELY jump down to END-OF-SWITCH
	


  case checkForBucketInPosition: only in case myStateVar == checkForBucketInPosition

    if ( (digitalRead(sensewaterstn) == beamBroken)); 
      digitalWrite(drive, LOW); // stop conveyor 	
      myStateVar = openWaterValve;
	}
	break; // skip other cases and IMMIDIATELY jump down to END-OF-SWITCH



  case openWaterValve: // only in case myStateVar == openWaterValve
  
    digitalWrite(waterfill, HIGH); 	
    WaterFillTimer = millis(); 
    myStateVar = wait5Seconds;
	break; // skip other cases and IMMIDIATELY jump down to END-OF-SWITCH



  case wait5Seconds: // only in case myStateVar == wait5Seconds
  
    if ( TimePeriodIsOver(WaterFillTimer, 5000) { 	
      myStateVar = closeWaterValve;
	}  
	break; // skip other cases and IMMIDIATELY jump down to END-OF-SWITCH



  case closeWaterValve: // only in case myStateVar == closeWaterValve
  
    digitalWrite(waterfill, LOW); 	
	myStateVar = waitForPressingStart;
	break; // skip other cases and IMMIDIATELY jump down to END-OF-SWITCH

  } // END-OF-SWITCH

Here is a tutorial how non-blocking timing works

Example-code for timing based on millis() easier to understand through the use of example-numbers / avoiding delay()

non-blocking timing. Execute code only from time to time. There are a lot of different ways to learn programming. This thread wants to add another approach that is different to the yet existing ones. UPDATE 06.01.2023 if you are mainly interested in applying non-blocking timing you can do a quick read of this short tutorial / demonstration If you are intersted in understanding the details how it works go on reading here. I use an everyday analogon in this post to explain the basic principle …

and here is a tutorial with a compiling demo-code that shows how state-machines work

A Demo-Code explaining the switch-case state-machine and how to do things (almost) in parallel

Hi everybody, if you look at the end of this first posting you see a list of links that show where this tutorial was used as a link. Go through this list to find additional information on how to apply this code This democode requires only the pure microcontroller without any hardware. You just open the serial monitor to watch the behaviour of the code. From time to time I enjoy writing demo-codes that want to explain programming-functionalities. There are a lot of different approachs to expl…

side-comment at @gcjr

You made a change that I appreciate.
You stayed somehow close on the code of the TO.

Still it is more or less your "standard-code" that has a huge lack of explaining things.
My opinion: you should add this standard comment to your code-suggestions.

Here is my version of a demo-code.
If you have questions you can ask as many questions as you like
If the my code is "above your head" skip my code-suggestion.