I got rid of your errors and warnings:
/*
Author: Krishna Agarwal
*/
#include <AFMotor.h>
//Objects
AF_DCMotor motorRight(1, MOTOR12_64KHZ); // create motor #1, 64KHz pwm
//Constants and variable
char dataIn = 'S';
char determinant;
char det;
int vel = 255; //Bluetooth Stuff
int god = 255;
int aod = 255;
int bod = 255;
int cod = 255;
int dod = 255;
void setup()
{
Serial.begin(9600); // set up Serial library at 9600 bps
//Initalization messages
Serial.println("ab");
Serial.println("ab");
Serial.println("ab");
pinMode(8, OUTPUT); //1 Led
pinMode(9, OUTPUT); //2 Led
pinMode(10, OUTPUT); //3 Led
pinMode(11, OUTPUT); //4 Led
pinMode(12, OUTPUT); //5 Led
//turn off motors
motorRight.setSpeed(0);
motorRight.run(RELEASE);
}
void loop()
{
det = check();
//serial code analysis
switch (det)
{
case 'F': // F, move forward
motorRight.setSpeed(vel);
motorRight.run(FORWARD);
det = check();
break;
case 'B': // B, move back
motorRight.setSpeed(vel);
motorRight.run(BACKWARD);
det = check();
break;
case 'L':// L, move wheels left
motorRight.setSpeed(vel / 4);
motorRight.run(FORWARD);
det = check();
break;
case 'R': // R, move wheels right
motorRight.setSpeed(vel / 2);
motorRight.run(FORWARD);
det = check();
break;
case 'S':
// S, stop
motorRight.setSpeed(vel);
motorRight.run(RELEASE);
det = check();
break;
case 'G':
// G, 1 Light On
digitalWrite(8, god);
det = check();
break;
case 'A':
// A, 2 Light on
digitalWrite(9, aod);
det = check();
break;
// case 'B': // DUPLICATE CASE
// // B, 3 Light on
// digitalWrite(10, bod);
// det = check();
// break;
case 'C':
// C, 4 Light On
digitalWrite(11, cod);
det = check();
break;
case 'D':
// D, 5 Light On
digitalWrite(12, dod);
det = check();
break;
case 'g':
// g, 1 Light off
digitalWrite(8, LOW);
det = check();
break;
case 'a':
// a, 2 Light off
digitalWrite(9, LOW);
det = check();
break;
case 'b':
// b, 3 Light off
digitalWrite(10, LOW);
det = check();
break;
case 'c':
// c, 4 Light On
digitalWrite(11, LOW);
det = check();
break;
case 'd':
// D, 5 Light Off
digitalWrite(12, LOW);
det = check();
break;
case 'Z':
// Z, All Light On
digitalWrite(8, god);
digitalWrite(9, aod);
digitalWrite(10, bod);
digitalWrite(11, cod);
digitalWrite(12, dod);
det = check();
break;
case 'z':
// z, All Light off
digitalWrite(8, LOW);
digitalWrite(9, LOW);
digitalWrite(10, LOW);
digitalWrite(11, LOW);
digitalWrite(12, LOW);
det = check();
break;
}
}
//get bluetooth code received from serial port
int check()
{
if (Serial.available() > 0) // if there is valid data in the serial port
{
dataIn = Serial.read();// stores data into a varialbe
//check the code
if (dataIn == 'F') //Forward
{
determinant = 'F';
}
else if (dataIn == 'B') //Backward
{
determinant = 'B';
}
else if (dataIn == 'L') //Left
{
determinant = 'L';
}
else if (dataIn == 'R') //Right
{
determinant = 'R';
}
else if (dataIn == 'S') //Stop motor
{
determinant = 'S';
}
else if (dataIn == 'G') //1 Light On
{
determinant = 'G';
}
else if (dataIn == 'A') //2 Light On
{
determinant = 'A';
}
else if (dataIn == 'B') //3 Light On
{
determinant = 'B';
}
else if (dataIn == 'C') //4 Light On
{
determinant = 'C';
}
else if (dataIn == 'D') //5 Light On
{
determinant = 'D';
}
else if (dataIn == 'g') //1 Light Off
{
determinant = 'g';
}
else if (dataIn == 'a') //2 Light off
{
determinant = 'a';
}
else if (dataIn == 'b') //3 Light Off
{
determinant = 'b';
}
else if (dataIn == 'c') //4 Light Off
{
determinant = 'c';
}
else if (dataIn == 'd') //5 Light off
{
determinant = 'd';
}
else if (dataIn == 'Z') //All Light On
{
determinant = 'Z';
}
else if (dataIn == 'z') //All light off
{
determinant = 'z';
}
else if (dataIn == '0') //Speed 0
{
vel = 0;
}
else if (dataIn == '1') //Speed 25
{
vel = 25;
}
else if (dataIn == '2') //Speed 50
{
vel = 50;
}
else if (dataIn == '3') //Speed 75
{
vel = 75;
}
else if (dataIn == '4') //Speed 100
{
vel = 100;
}
else if (dataIn == '5') //Speed 125
{
vel = 125;
}
else if (dataIn == '6') //Speed 150
{
vel = 150;
}
else if (dataIn == '7') //Speed 175
{
vel = 175;
}
else if (dataIn == '8') //Speed 200
{
vel = 200;
}
else if (dataIn == '9') //Speed 225
{
vel = 225;
}
// else if (dataIn == '11') //Led 0 // dataIn CAN'T HOLD TWO CHARACTERS
// {
// god = 0;
// }
// else if (dataIn == '12') //Led 25
// {
// god = 25;
// }
// else if (dataIn == '13') //Led 50
// {
// god = 50;
// }
// else if (dataIn == '14') //Led 75
// {
// god = 75;
// }
// else if (dataIn == '15') //Led 100
// {
// god = 100;
// }
// else if (dataIn == '16') //Led 125
// {
// god = 125;
// }
// else if (dataIn == '17') //Led 150
// {
// god = 150;
// }
// else if (dataIn == '18') //Led 200
// {
// god = 200;
// }
// else if (dataIn == '19') //Led 255
// {
// god = 255;
// }
}
return determinant;
}