Question about project

Projects General Guidance
1

I need to read a value off of a potentiometer which will be 0 - 5V. I then need to assign a variable so it is 1 of 23 based on the voltage at the pot. Basically you turn the handle on the pot and it counts from 1 to 23 as you turn it.
I am then going to have that value trigger a nixie display that counts from 1 to 23. is there a function like a table I could fill out assigning the ranges for each position to keep from having 24 if statements?

2

Look into the Arduino reference and search for the map function!

3 
int val = analogRead(potPin) / 44;
4 
int analogValue = analogRead(potPin) 
int count = map(analogValue, 0, 1023, 0, 23);

See Arduino - map() function

5 
void setup()
{
  Serial.begin(9600);
}
void loop()
{
  int val = analogRead(A0) / 44;
  Serial.println(val);
  delay(500);  
}

Sketch uses 2452, bytes (7%) of program storage space.

void setup()
{
  Serial.begin(9600);
}
void loop()
{
  int analogValue = analogRead(A0);
  int count = map(analogValue, 0, 1023, 0, 23);
  Serial.println(count);
  delay(500);  
}

Sketch uses 2,744 bytes (8%) of program storage space.

Difference, 292 bytes, map can be expensive. :wink:

6

My worry about the map function is that how it works is not transparent

However it does simplify the actual math. (Thanks Erik!)

7

jwags818:
I am then going to have that value trigger a nixie display that counts from 1 to 23. is there a function like a table I could fill out assigning the ranges for each position to keep from having 24 if statements?

IoT_hobbyist:

int analogValue = analogRead(potPin)

int count = map(analogValue, 0, 1023, 0, 23);



See [Arduino - map() function](https://arduinogetstarted.com/reference/arduino-map)

Make that:

int count = map(analogValue, 0, 1023, 1, 23);
8

johnerrington:
My worry about the map function is that how it works is not transparent

You have the source, and it's described here

9

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