#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>

// === FPGA side ===
#define HW_REGS_BASE ( 0xff200000 )
#define HW_REGS_SPAN ( 0x00200000 )
#define HW_REGS_MASK ( HW_REGS_SPAN - 1 )
#define LED_PIO_BASE 0x00
#define HEX_PIO_BASE 0x10
int hex_lut[]={0x40, 0x79, 0x24, 0x30, 0x19, 0x12, 0x02, 0x78,
               0x00, 0x10, 0x08, 0x03, 0x46, 0x21, 0x06, 0x0e};
// === HPS side ===
#define GPIO1_BASE 0xFF709000
#define GPIO1_EXT_OFFSET 0x14
// the bit position of the switch
#define bit_25 0x02000000
// ===============

int main(void)
{
    // === FPGA ===
    volatile unsigned int *h2p_lw_led_addr=NULL;
    volatile unsigned int *h2p_lw_hex_addr=NULL;
    void *h2p_lw_virtual_base;
    int fd;
    // === HPS switch ===
    volatile unsigned int *led_addr=NULL;
    void *virtual_base_gpio;
    int fd1 ;
    // ================= 
     volatile int i;
    
    // === get FPGA addresses ===
    // Open /dev/mem
	if( ( fd = open( "/dev/mem", ( O_RDWR | O_SYNC ) ) ) == -1 ) {
		printf( "ERROR: could not open \"/dev/mem\"...\n" );
		return( 1 );
	}
    
    // get virtual addr that maps to physical
	h2p_lw_virtual_base = mmap( NULL, HW_REGS_SPAN, ( PROT_READ | PROT_WRITE ), MAP_SHARED, fd, HW_REGS_BASE );	
	if( h2p_lw_virtual_base == MAP_FAILED ) {
		printf( "ERROR: mmap() failed...\n" );
		close( fd );
		return(1);
	}
    
    // Get the address that maps to the FPGA LED control 
	h2p_lw_led_addr=(unsigned int *)(h2p_lw_virtual_base + (( LED_PIO_BASE ) & ( HW_REGS_MASK ) ));
    
    // get address for hex display offset 0x10
        h2p_lw_hex_addr=(volatile unsigned int *)(h2p_lw_virtual_base+0x10);

    // === get HPS GPIO1 address ===
    // Open /dev/mem
        if( ( fd1 = open( "/dev/mem", ( O_RDWR | O_SYNC ) ) ) == -1 ) {
                printf( "ERROR: could not open \"/dev/mem\"...\n" );
                return( 1 );
        }

    // get virtual addr that maps to physical
        virtual_base_gpio = mmap( NULL, 0x1000, ( PROT_READ | PROT_WRITE ), MAP_SHARED, fd1, GPIO1_BASE );
        if( virtual_base_gpio == MAP_FAILED ) {
                printf( "ERROR: mmap() failed...\n" );
                close( fd1);
                return(1);
        }

    //Get the address that maps to the GPIO base
        led_addr=(volatile unsigned int *)(virtual_base_gpio);

    // =============================
    // read the GPIO input register at led_addr+0x14
    // led_addr happens to be at offset zero from GPIO base address
    int step;
    while(1){
	printf(">");
	scanf("%d", &step);
    	*h2p_lw_led_addr = step ;
	// 8-bits per digit output
        *h2p_lw_hex_addr = hex_lut[step & 0xf]+
			    (hex_lut[(step>>4) & 0xf]<<8);
    	//*h2p_lw_led_addr =  ((int)*(led_addr+0x14)& bit_25 )>>24  ;
    //   printf("%x\n",((int)*(led_addr+0x14)& bit_25)>>25);

    }	

   // close( fd1);
   return 0;
}