Counter with limits

Projects Programming
6

Hello,
take a view to CONSTRAIN instruction inside the Arduino reference.

Try this and ckeck it out for your project:

// BLOCK COMMENT
// https://www.learncpp.com/cpp-tutorial/
// https://forum.arduino.cc/t/counter-with-limits/903228
#define ProjectName "Counter with limits"
// CONSTANT DEFINITION
// you may need to change these constants to your hardware and needs
constexpr byte Input_[] {A0, A1};
constexpr unsigned long  ScanButtonTime {20};
// VARIABLE DECLARATION AND DEFINTION
enum {OctavaUp , OctavaDown };
unsigned long currentTime;
struct TIMER {
  unsigned long duration;
  unsigned long stamp;
};
TIMER scanButton{ScanButtonTime, 0};
struct BUTTON {
  int name_;
  byte pin;
  bool state_;
} buttons[] {
  {OctavaUp, Input_[OctavaUp], 0},
  {OctavaDown, Input_[OctavaDown], 0},
};
int octavas {3};

// FUNCTIONS
bool checkTimer(TIMER & time_) {
  if (currentTime - time_.stamp >= time_.duration ) {
    time_.stamp = currentTime;
    return true;
  } else return false;
}

void setup() {
  Serial.begin(9600);
  Serial.println(F("."));
  Serial.print(F("File   : ")), Serial.println(__FILE__);
  Serial.print(F("Date   : ")), Serial.println(__DATE__);
  Serial.print(F("Project: ")), Serial.println(ProjectName);
  pinMode (LED_BUILTIN, OUTPUT);
  for (auto Input : Input_) pinMode(Input, INPUT_PULLUP);
  Serial.println(octavas);
}
void loop () {
  currentTime = millis();
  digitalWrite(LED_BUILTIN, (currentTime / 500) % 2);
  if (currentTime - scanButton.stamp >= scanButton.duration) {
    scanButton.stamp = currentTime;
    for (auto &button_ : buttons) {
      bool stateNew = !digitalRead(button_.pin);
      if (button_.state_ != stateNew) {
        button_.state_ = stateNew;
        if (stateNew)  {
          switch (button_.name_) {
            case OctavaUp:
              octavas++;
              break;
            case OctavaDown:
              octavas--;
              break;
          }
          octavas = constrain(octavas, 0, 6);
          Serial.println(octavas);
        }
      }
    }
  }
}

Have a nice day and enjoy coding.