ESP32 Problem with rotary encoder

[suntchi56]

Environment: Arduino ver. 1.8.19 - ESP32 WOROOM 38pin
I created this routine for the rotary encoder, but I have a problem.
I can't get the requested values.
If I use a min_val = 1 and a max_val = 10 I have no problems the values go from the minimum to the maximum allowed value, cycling from the minimum to the maximum and vice versa.
But if I use min_val = 0 and max_val = 10 when going below zero I get the maximum value allowed for an unsigned int.
I can't figure it out, is anyone able to fix this?

// 
#define ENC_A   17                 // Rotary encoder parameters
#define ENC_B   16                 // Rotary encoder parameters

unsigned int counter = 0;
unsigned int lastCounter = 1;
unsigned int min_val = 1;
unsigned int max_val = 10;

void setup() {

  Serial.begin(115200);
  while(!Serial) {}                    // Wait for Serial port
  delay(1000);
  pinMode(ENC_A,  INPUT_PULLUP);       // Rotary encoder pins
  pinMode(ENC_B,  INPUT_PULLUP);       // Rotary encoder pins
}

void loop() {
 
     read_encoder();
     if (counter != lastCounter) {
        Serial.println(counter);
     }
     lastCounter = counter;
}

void read_encoder() {
 
  static uint8_t old_AB = 3;  // Lookup table index
  static int8_t encval = 0;   // Encoder value  
  static const int8_t enc_states[]  = {0,-1,1,0,1,0,0,-1,-1,0,0,1,0,1,-1,0}; // Lookup table

  old_AB <<= 2;  // Remember previous state

  if (digitalRead(ENC_A)) old_AB |= 0x02; // Add current state of pin A
  if (digitalRead(ENC_B)) old_AB |= 0x01; // Add current state of pin B
  
  encval += enc_states[( old_AB & 0x0f )];

  // Update counter if encoder has rotated a full indent, that is at least 4 steps
  if( encval >= 3 ) {         // Four steps forward
    counter++;               // Increase counter
    if (counter > max_val) {counter = min_val;}
    encval = 0;
  }
  else if( encval <= -3 ) {   // Four steps backwards
    counter--;               // Decrease counter
    if (counter < min_val) {counter = max_val;}
    encval = 0;
  }
}

[johnerrington]

The code is little use without a schematic

How to make a schematic you can post.

When you submit a question on the forum you will usually need to add a schematic (circuit diagram). The tutorial that follows will explain some ways to create a useful image; however lets start by explaining how to add the image to your post. Its easy. Having created the image all you need to do is : Save the image somewhere convenient - maybe your desktop Start your post, and place the cursor (insertion point) where you want the image to be shown; [upload image to forum] 3: click th…

@suntchi56

rotary encoder

and a link to the data sheet fot the devices used.

However

But if I use min_val = 0 and max_val = 10 when going below zero I get the maximum value allowed for an unsigned int

.

yes because -1 = the maximum value allowed for an unsigned int.

[suntchi56]

Sorry me for the missing pattern and thanks for waking me up !!
You cleared everything up for me, thank you very much.