I’ve an Arduino venture to manage a motor’s velocity at 3 ranges, indicated by 3 LEDs, so degree 1 is velocity 1 and LED 1, and so forth for ranges 2/3.

Additionally, I added a low-battery voltage indicator to watch the battery degree.

I’m going to make use of an ATtiny45, which has 8 pins(Vcc, GND, 1 analog pin, 5 digital pins). The venture wants 6 digital pins and 1 analog pin, so just one extra pin is required.

I don’t need to use an expander or I2C, as they are going to make the venture extra advanced, and it’s only one pin!

I can use a bigger microcontroller however it will be the final selection.

Right here is my venture’s diagram and code:

//********************************************^************************************************
//  https://discussion board.arduino.cc/t/control-motor-speed-with-npn-and-push-button-no-driver/1184925
//
//
//
//  Model    YY/MM/DD    Feedback
//  =======    ========    ====================================================================
//  1.00       20/23/02    Operating code
//  1.10       20/23/03    Added motor and LEDs OFF if change pressed for >= 3 sec.
//
//
//

#outline PRESSED            HIGH
#outline RELEASED           LOW

#outline ENABLED            true
#outline DISABLED           false

#outline LEDon              HIGH
#outline LEDoff             LOW

#outline MOTORoff           0

#outline lipo               A0

float lipoV = 0;

//GPIOs
const byte Button        = 2;
const byte ledpin        = 3;
const byte ledpin1       = 4;
const byte ledpin2       = 5;
const byte Motor         = 9;
const byte heartbeatLED  = 13;
const byte Pink           = 6;

//Variables
byte lastButton          = RELEASED;
byte currSwitch;

int Speed_Level;

bool bCheckingSwitch     = DISABLED;

//timing stuff
unsigned lengthy heartbeatTime;
unsigned lengthy switchesTime;
unsigned lengthy threeSecondTime;

//                                      s e t u p ( )
//********************************************^************************************************
void setup()
{
  pinMode(Button, INPUT);
  pinMode(lipo, INPUT);

  pinMode(ledpin, OUTPUT);
  pinMode(ledpin1, OUTPUT);
  pinMode(ledpin2, OUTPUT);
  pinMode(Motor, OUTPUT);
  pinMode(heartbeatLED, OUTPUT);
  pinMode(Pink, OUTPUT);
  

} //END of   setup()


//                                       l o o p ( )
//********************************************^************************************************
void loop()
{

  //************************************************              T I M E R  heartbeatLED

  //is it time to toggle the heartbeat LED ?
  if (millis() - heartbeatTime >= 500ul)
  {

    //restart this TIMER
    heartbeatTime = millis();

    //toggle the heartbeat LED
    if (digitalRead(heartbeatLED) == HIGH) digitalWrite(heartbeatLED, LOW);
    else digitalWrite(heartbeatLED, HIGH);
  }

  //************************************************              T I M E R  verify switches
  //is it time to verify our switches ?
  if (millis() - switchesTime >= 50ul)
  {
    //restart this TIMER
    switchesTime = millis();

    checkSwitches();
  }

  //************************************************              T I M E R  three seconds
  //if enabled, is it time to show issues OFF ?
  if (bCheckingSwitch == ENABLED && millis() - threeSecondTime >= 2000ul)
  {
    //we're completed with this TIMER
    bCheckingSwitch = DISABLED;

    //restart the sequence
    Speed_Level = -1;

    analogWrite(Motor, MOTORoff);
    digitalWrite(ledpin, LEDoff);
    digitalWrite(ledpin1, LEDoff);
    digitalWrite(ledpin2, LEDoff);
    digitalWrite(Pink, LEDoff);
  }

} //END of   loop()


//                               c h e c okay S w i t c h e s ( )
//********************************************^************************************************
void checkSwitches()
{
  byte state;

  //************************************************              Button
  state = digitalRead(Button);

  //has there been a state change within the change ?
  if (lastButton != state)
  {
    //replace to the brand new state
    lastButton = state;

    //*******************************
    if (state == PRESSED)
    {
      //allow the TIMER
      bCheckingSwitch = ENABLED;

      //begin the TIMER
      threeSecondTime = millis();
    }

    //*******************
    //the change was launched
    else
    {
      //disable the TIMER
      bCheckingSwitch = DISABLED;

      Speed_Level++;
      lipoV = analogRead(lipo);

      //battery checker
      if(lipoV < 680){
        digitalWrite(Pink,LEDon);
      }

       else
       {
        digitalWrite(Pink,LEDoff);
    
       }

      //do not go over 3
      if (Speed_Level >= 4)
      {
        Speed_Level = 0;
      }

      //*******************
      if (Speed_Level == 1)
      {
        analogWrite(Motor, 50);
        digitalWrite(ledpin, LEDon);
        digitalWrite(ledpin1, LEDoff);
        digitalWrite(ledpin2, LEDoff);
      }

      //*******************
      else if (Speed_Level == 2)
      {
        analogWrite(Motor, 75);
        digitalWrite(ledpin, LEDoff);
        digitalWrite(ledpin1, LEDon);
        digitalWrite(ledpin2, LEDoff);
      }

      //*******************
      else if (Speed_Level == 3)
      {
        analogWrite(Motor, 100);
        digitalWrite(ledpin, LEDoff);
        digitalWrite(ledpin1, LEDoff);
        digitalWrite(ledpin2, LEDon);
      }

      //*******************
      else
      {
        analogWrite(Motor, MOTORoff);
        digitalWrite(ledpin, LEDoff);
        digitalWrite(ledpin1, LEDoff);
        digitalWrite(ledpin2, LEDoff);
        digitalWrite(Pink,LEDoff);
      }

  }

}
}//END of   checkSwitches()

//********************************************^************************************************

Can I take advantage of tA0 as enter and output on the similar time like this?

Or can I cut back the LED pins, that means use 1 pins for two LEDs?