DC Motor become stop with directional Command

Hi,I have created a program to speed and directional control of DC motor, currently when I entered the directional command"forward" or "reverse" through serial terminal then the analog out become zero for speed control.

#define SV 10
#define FR 9
#define BRK 8
#define EN 7
int encoderpin = 2;
unsigned int rpm ;
volatile byte pulses;
unsigned long timeold;
unsigned int pulsesperturn=6;
int readNumber;
int pwmOutput;
String a;
void counter()
{
  pulses++;
}
void setup() {
  // put your setup code here, to run once:
Serial.begin(9600);
pinMode(SV, OUTPUT);
pinMode(FR,OUTPUT);
pinMode(BRK,OUTPUT);
pinMode(EN,OUTPUT);
pinMode(encoderpin, INPUT);
analogWrite(SV, 255);
digitalWrite(FR, HIGH);
digitalWrite(BRK, LOW);
digitalWrite(EN, LOW);
attachInterrupt(0,counter,FALLING);
pulses=0;
rpm=0;
timeold=0;
}

void loop() {
  // put your main code here, to run repeatedly:
if (Serial.available()>1){
  a= Serial.readString();
  if(a=="Forward"){
	digitalWrite(FR, HIGH);
	digitalWrite(BRK, HIGH);
    delay(200);
  }
  if(a=="Reverse"){
	digitalWrite(FR, LOW);
	digitalWrite(BRK, HIGH);
    delay(200);
  }
  if(a=="Stop"){
	digitalWrite(BRK, HIGH);
    delay(200);
  }
   else{
     readNumber=a.toInt();
     if (readNumber>=0 && readNumber<=100)
     {
      pwmOutput=map(readNumber,0,100,0,255);
      analogWrite(SV,pwmOutput);
     }
  }
}
if (millis()-timeold>=1000){
  detachInterrupt(0);
  rpm = (60000/(millis()-timeold))*pulses;
  rpm=rpm/4;
  timeold= millis();
  pulses=0;
  Serial.println(rpm,DEC);
  attachInterrupt(0,counter,FALLING);
 }
}

Welcome to the Arduino forum. I am sorry you have had problems with your project, but for anyone to help you need to give more information, such as how are you powering the motor, are you stopping the motor before you change directions, and a block diagram showing what you have and how it is all connected. How much current does the motor take?
Paul

Set line endings in serial monitor to "No line ending". "Forward" is not equal to "Forward\r\n".

But it's changing the status of pins successfully but with also changed the SV(analog pin) value to zero

@raih101, your topic has been moved to a more suitable location on the forum; see About the Installation & Troubleshooting category :wink:

It will be surprised that someone help me to find the actual issue