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#include "TM4C123GH6PM.h"
unsigned int value;
void delayMs(int n)
{
    int i, j;
    for(i = 0 ; i < n; i++)
        for(j = 0; j < 3180; j++)
            {}  /* do nothing for 1 ms */
}
int main(void)
{   
    RCGCGPIO |= 0x20;   
    //or SYSCTL->RCGCPIO |= 0x20;
    GPIOF ->DIR = 0x0E;
    GPIOF ->DEN = 0x1E;         /* and PORTF4 as input, SW1 is on PORTF4 */
           /* set PORTF pins 4-3 as digital pins */
    GPIOF->PUR = 0x10;          /* enable pull up for pin 4 */
    while(1)
    {   
        value = GPIOF->DATA;    /* read data from PORTF */
    if(!value){
    GPIOF->DATA = 0x02;
    delay(500);
    GPIOF->DATA = 0x08;
    delay(500);
    GPIOF->DATA = 0x04;
    delay(500);
    GPIOF->DATA = 0x00;
    delay(500);
    GPIOF->DATA = 0x04;
    delay(500);
    GPIOF->DATA = 0x08;
    delay(500);
    GPIOF->DATA = 0x02;
    delay(500);
    GPIOF->DATA = 0x00;
    delay(500);
    }

    }
}


void SystemInit(void)
{
    SCB->CPACR |= 0x00F00000;
}