Driving a car toy with L293D

Using Arduino Motors, Mechanics, Power and CNC
#1

Okay guys I am trying to drive a toy car I found with L293D and this is the simple code I made

const int in1Pin = 5; 
const int in2Pin = 4;
const int in3Pin = 3; r
const int in4Pin = 2;

void stopMotors(void);
void rearWheelsForwards(void);
void rearWheelsBackswards(void);
void frontWheelsRight(void);
void frontWheelsLeft(void);

void setup()
{
  Serial.begin(9600);
  pinMode(in1Pin, OUTPUT);
  pinMode(in2Pin, OUTPUT);
  pinMode(in3Pin, OUTPUT);
  pinMode(in4Pin, OUTPUT);

  pinMode(ledPin,OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(trigPin, OUTPUT);
  
  Serial.println("1 - forwards , 2 - backwards, 3 - left , 4 - right");
}

void loop()
{
 
  if ( Serial.available()) {
    char ch = Serial.read();
    
    if (ch == '1')
    {
      Serial.println("CW");
      rearWheelsForwards();
    }
    else if (ch == '2' )
    {
      Serial.println("CCW");
      rearWheelsBackwards();
    }
    else if( ch == '3')
    {
      Serial.println("Left");
      frontWheelsLeft();  
    }
    else if( ch == '4'){
      Serial.println("Right");
      frontWheelsRight();
    }
    else if( ch == '0'){
      stopMotors();
    }
  }
}

void stopMotors(void){
  
    digitalWrite(in1Pin,LOW);
    digitalWrite(in2Pin,LOW);
    digitalWrite(in3Pin,LOW);
    digitalWrite(in4Pin,LOW);
    Serial.println("Motors stopped!");
}

void rearWheelsForwards(void){
  
   digitalWrite(in1Pin,LOW);
   digitalWrite(in2Pin,HIGH);
}

void rearWheelsBackwards(void){
  
   digitalWrite(in1Pin,HIGH);
   digitalWrite(in2Pin,LOW); 
}

void frontWheelsRight(void){
  
   digitalWrite(in3Pin,LOW);
   digitalWrite(in4Pin,HIGH);
}

void frontWheelsLeft(void){
   
   digitalWrite(in3Pin,HIGH);
   digitalWrite(in4Pin,LOW);
}

I tried calling functions without Serial input and it worked just fine , but with this piece of code it just doesnt work, not quite sure why is this happening.

l293d.JPG

#2 
const int in3Pin = 3; r
const int in4Pin = 2;

Your code doesn't compile, so I don't know how you can say whether it "works" or not.

#3

Your code as posted has syntax errors and undeclared variables.

Please post the actual code that is failing together with a careful explanation of what
it should do and in what way it isn't working.

#4

AWOL:

const int in3Pin = 3; r

const int in4Pin = 2;



Your code doesn't compile, so I don't know how you can say whether it "works" or not.

I added this accidentally when posting a code here

MarkT:
Your code as posted has syntax errors and undeclared variables.

Please post the actual code that is failing together with a careful explanation of what
it should do and in what way it isn't working.

Those variables that are not declared were part of HC - SR04 detecting if a car is going to some object and making car to stop so it doesnt hit any object, forgot to delete it.

const int in1Pin = 5; 
const int in2Pin = 4;
const int in3Pin = 3; 
const int in4Pin = 2;

void stopMotors(void);
void rearWheelsForwards(void);
void rearWheelsBackswards(void);
void frontWheelsRight(void);
void frontWheelsLeft(void);

void setup()
{
  Serial.begin(9600);
  pinMode(in1Pin, OUTPUT); // first motor pin
  pinMode(in2Pin, OUTPUT);  // first motor pin
  pinMode(in3Pin, OUTPUT);  // second motor pin
  pinMode(in4Pin, OUTPUT); // second motor pin

  Serial.println("1 - forwards , 2 - backwards, 3 - left , 4 - right");
}

void loop()
{
 
  if ( Serial.available()) {
    char ch = Serial.read();
    
    if (ch == '1')
    {
      Serial.println("CW");
      rearWheelsForwards(); // makes rear DC motor go CW ,so car moves forward
    }
    else if (ch == '2' )
    {
      Serial.println("CCW");
      rearWheelsBackwards(); // makes rear DC motor go CCW ,so car moves backwards
    }
    else if( ch == '3')
    {
      Serial.println("Left");
      frontWheelsLeft();  // makes front DC motor go left, so car turns left side
    }
    else if( ch == '4'){
      Serial.println("Right");
      frontWheelsRight(); // makes front DC motor go right, so car turns left side
    }
    else if( ch == '0'){
      stopMotors(); // if '0' is pressed car just shuts down all the motors
    }
  }
}

void stopMotors(void){
  
    digitalWrite(in1Pin,LOW);
    digitalWrite(in2Pin,LOW);
    digitalWrite(in3Pin,LOW);
    digitalWrite(in4Pin,LOW);
    Serial.println("Motors stopped!");
}

void rearWheelsForwards(void){
  
   digitalWrite(in1Pin,LOW);
   digitalWrite(in2Pin,HIGH);
}

void rearWheelsBackwards(void){
  
   digitalWrite(in1Pin,HIGH);
   digitalWrite(in2Pin,LOW); 
}

void frontWheelsRight(void){
  
   digitalWrite(in3Pin,LOW);
   digitalWrite(in4Pin,HIGH);
}

void frontWheelsLeft(void){
   
   digitalWrite(in3Pin,HIGH);
   digitalWrite(in4Pin,LOW);
}
#5

Okay restarted the IDE and reuploaded code and it works, really strange.
Thank you anyways.

#6