// BranchingFunctionsDelays.c Lab 6
// Runs on LM4F120/TM4C123
// Use simple programming structures in C to
// toggle an LED while a button is pressed and
// turn the LED on when the button is released.
// This lab will use the hardware already built into the LaunchPad.
// Daniel Valvano, Jonathan Valvano
// January 15, 2016

// built-in connection: PF0 connected to negative logic momentary switch, SW2
// built-in connection: PF1 connected to red LED
// built-in connection: PF2 connected to blue LED
// built-in connection: PF3 connected to green LED
// built-in connection: PF4 connected to negative logic momentary switch, SW1

#include "TExaS.h"

#define GPIO_PORTF_DATA_R       (*((volatile unsigned long *)0x400253FC))
#define GPIO_PORTF_DIR_R        (*((volatile unsigned long *)0x40025400))
#define GPIO_PORTF_AFSEL_R      (*((volatile unsigned long *)0x40025420))
#define GPIO_PORTF_PUR_R        (*((volatile unsigned long *)0x40025510))
#define GPIO_PORTF_DEN_R        (*((volatile unsigned long *)0x4002551C))
#define GPIO_PORTF_AMSEL_R      (*((volatile unsigned long *)0x40025528))
#define GPIO_PORTF_PCTL_R       (*((volatile unsigned long *)0x4002552C))
#define SYSCTL_RCGC2_R          (*((volatile unsigned long *)0x400FE108))
#define SYSCTL_RCGC2_GPIOF      0x00000020  // port F Clock Gating Control

// Global Variables
unsigned long SW1;

// basic functions defined at end of startup.s
void DisableInterrupts(void); // Disable interrupts
void EnableInterrupts(void);  // Enable interrupts
void Delay100ms(unsigned long time);
void PortF_Init(void);

int main(void){ unsigned long volatile delay;
  TExaS_Init(SW_PIN_PF4, LED_PIN_PF2);  // activate grader and set system clock to 80 MHz
  // initialization goes here
    PortF_Init();        // Call initialization of port PF2

  EnableInterrupts();           // enable interrupts for the grader
    GPIO_PORTF_DATA_R = 0x04;
  while(1){
        SW1 = GPIO_PORTF_DATA_R&0x10;
    // body goes
        Delay100ms(1);
        if(SW1)
        {
            GPIO_PORTF_DATA_R ^= 0x04;
        }
        else
        {
            GPIO_PORTF_DATA_R = 0x04;
        }
  }
}
void Delay100ms(unsigned long time){
  unsigned long i;
  while(time > 0){
    i = 1333333;  // this number means 100ms
    while(i > 0){
      i = i - 1;
    }
    time = time - 1; // decrements every 100 ms
  }
}
void PortF_Init(void){ volatile unsigned long delay;
  SYSCTL_RCGC2_R |= 0x00000020;     // 1) F clock
  delay = SYSCTL_RCGC2_R;           // delay
  GPIO_PORTF_AMSEL_R = 0x00;        // 3) disable analog function
  GPIO_PORTF_PCTL_R = 0x00000000;   // 4) GPIO clear bit PCTL
  GPIO_PORTF_DIR_R = 0x0E;          // 5) PF4,PF0 input, PF3,PF2,PF1 output
  GPIO_PORTF_AFSEL_R = 0x00;        // 6) no alternate function
  GPIO_PORTF_PUR_R = 0x11;          // enable pullup resistors on PF4,PF0
  GPIO_PORTF_DEN_R = 0x1F;          // 7) enable digital pins PF4-PF0
}