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//Program to 


#include<avr/io.h>
#include<util/delay.h>
 
#define F_CPU 1000000
 
#define USART_BAUDRATE 9600
#define BAUD_PRESCALE (((F_CPU / (USART_BAUDRATE*16UL))) - 1)
 
#define pad PORTA
#define r1 PA0
#define r2 PA1
#define r3 PA2
#define r4 PA3
 
#define c1 PA4
#define c2 PA5
#define c3 PA6
 
 
// Function prototype to check key pressed from keypad 
void check1(void);
void check2(void);  
void check3(void);
void check4(void);
 
#define LCD_DATA PORTB //LCD data port
 
#define ctrl PORTD
#define en PD2 //enable signal
#define rw PD1 //read/write signal
#define rs PD0 //resister select signal
 
#define CONTROL_OUTPUT PORTC // output port for wireless transmission
 
void LCD_cmd(unsigned char cmd);
void init_LCD(void);
void LCD_write(unsigned char data);
 
void move_forward();
void move_backward();
void turn_left();
void turn_right();
 
unsigned int press;
 
int main()
{
    unsigned char value; 
    DDRC=0x0f; //LCD_DATA port as output port
    DDRB=0xFF; //signal
    DDRA = 0X0F;
    DDRD = 0X07; 
 
    pad = 0xF0;
    init_LCD(); //initialization of LCD
    _delay_ms(50);
    LCD_write_string("EngineersGarage");
    _delay_ms(1000);
    LCD_cmd(0x01);
    LCD_write_string("Keypad Cntrld");
    LCD_cmd(0xC0);
    LCD_write_string("Wireless Robot");
 
    while(1)
    {
PORTA=0xF0; //set all the input to one
value=PINA; //get the PORTD value in variable “value”
if(value!=0xf0) //if any key is pressed value changed
{
    check1();
    check2();
    check3();
    check4();
}
    }
    return 0;
}
 
void check1(void)
{
    pad =0b11111110;
    _delay_us(10);
 
    if(bit_is_clear(PINA,c2))
    {
move_forward();
    }
}
 
 
void check2(void)
{
    pad=0b11111101;
    _delay_us(10);
 
    if(bit_is_clear(PINA,c3))
    {
turn_right();
    }
}
 
void check3(void)
{
    pad=0b11111011;
    _delay_us(10);
 
    if(bit_is_clear(PINA,c2))
    {
move_backward();
    }
}
 
void check4(void)
{
    pad =0b11110111;
    _delay_us(10);
 
    if(bit_is_clear(PINA,c2))
    {
robo_stop();
    }
}
 
 
 
void init_LCD(void)
{
 
    LCD_cmd(0x38); //initializtion of 16X2 LCD in 8bit mode
    _delay_ms(1);
 
    LCD_cmd(0x01); //clear LCD
    _delay_ms(1);
 
    LCD_cmd(0x0E); //cursor ON
    _delay_ms(1);
 
    LCD_cmd(0x80); // ---8 go to first line and --0 is for 0th position
    _delay_ms(1);
    return;
}
 
 
void LCD_cmd(unsigned char cmd)
{
    LCD_DATA=cmd;
    ctrl =(0<<rs)|(0<<rw)|(1<<en); // making RS and RW as LOW and EN as HIGH
    _delay_ms(1);
    ctrl =(0<<rs)|(0<<rw)|(0<<en); // making RS, RW , LOW and EN as LOW
    _delay_ms(50);
    return;
}
 
 
void LCD_write(unsigned char data)
{
    LCD_DATA= data;
    ctrl = (1<<rs)|(0<<rw)|(1<<en); // making RW as LOW and RS, EN as HIGH
    _delay_ms(1);
    ctrl = (1<<rs)|(0<<rw)|(0<<en); // making EN and RW as LOW and RS HIGH
    _delay_ms(50); // give a 10 milli second delay to get thigs executed
    return ;
}
 
void LCD_write_string(unsigned char *str) //take address vaue of the string in pionter *str
{
    int i=0;
    while(str[i]!='') // loop will go on till the NULL charaters is soon in string 
    {
LCD_write(str[i]); // sending data on CD byte by byte
i++;
    }
    return;
}
 
void move_forward()
{
    LCD_cmd(0x01); //clear LCD
    LCD_write_string("   Direction");
    LCD_cmd(0xc0);
    LCD_write_string("Moving Forward");
    CONTROL_OUTPUT = 0x05;
}
 
void move_backward()
{
    LCD_cmd(0x01); //clear LCD
    LCD_write_string("   Direction");
    LCD_cmd(0xc0);
    LCD_write_string("Moving Backward");
    CONTROL_OUTPUT = 0x0A;
}
 
void turn_left()
{
    LCD_cmd(0x01); //clear LCD
    LCD_write_string("   Direction");
    LCD_cmd(0xc0);
    LCD_write_string("Turning Left");
    CONTROL_OUTPUT = 0x08;
}
 
void turn_right()
{
    LCD_cmd(0x01); //clear LCD
    LCD_write_string("   Direction");
    CONTROL_OUTPUT = 0x01;
    LCD_cmd(0xc0);
    LCD_write_string("Turning Right");
}
 
void robo_stop()
{
    LCD_cmd(0x01); //clear LCD
    LCD_write_string("   Direction");
    CONTROL_OUTPUT = 0x00;
    LCD_cmd(0xc0);
    LCD_write_string("     STOP");
}
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