/* Author : Gaurav Sharma h2016075@pilani.bits-pilani.ac.in
						Himanshu Shekhar h2016071@pilani.bits-pilani.ac.in. */


#ifndef EXT_INT_H
#define EXT_INT_H

#include <lpc214x.h>
#include <stdint.h>
#define EXTINT_EINT2_MASK 0x4
#define EXTMODE_EXTMODE2_MASK 0x0
#define EXTPOLAR_EXTPOLAR2_MASK 0x4

// Vector Control Register bit definitions
#define VIC_ENABLE      (1 << 5)

// Convert Channel Number to Bit Value
#define VIC_BIT(chan)   (1 << (chan))
#define VIC_EINT2       16

volatile uint8_t boolean_value=0;
void Ext_ISR(void) __irq;
void init_ext_interrupt()
{
	boolean_value = 0;
  EXTMODE = EXTMODE_EXTMODE2_MASK;
  
  EXTPOLAR &= ~EXTPOLAR_EXTPOLAR2_MASK;

  PINSEL0 = (PINSEL0 & ~(3 << 30)) | (1 << 31);
  
  /* initialize the interrupt vector */
  VICIntSelect &= ~ VIC_BIT(VIC_EINT2);           // EINT0 selected as IRQ
  VICVectAddr5 = (unsigned int)Ext_ISR;        // address of the ISR
  VICVectCntl5 = VIC_ENABLE | VIC_EINT2;
  VICIntEnable = VIC_BIT(VIC_EINT2);              // EINT0 interrupt enabled

  EXTINT &= ~EXTINT_EINT2_MASK;	
}

void enable_signal() {
	boolean_value = 1;
}

void disable_signal() {
	boolean_value = 0;
}
uint8_t get_signal() {
	return boolean_value;
}

void Ext_ISR(void) __irq
{

	enable_signal();
	EXTINT |= EXTINT_EINT2_MASK;                                 //clear interrupt
	VICVectAddr = 0; 
}

#endif