#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#define DATA_PORT 0x378 /* parallel port base address */
#define STATUS_PORT DATA_PORT + 1
#define CONTROL_PORT DATA_PORT + 2

unsigned char status, data;

// Array to hold bit patterns for each digit
unsigned char BCD_values[10] = {
        0b00000000, // digit 0
        0b00000001, // digit 1
        0b00000010, // digit 2
        0b00000011, // digit 3
        0b00000100, // digit 4
        0b00000101, // digit 5
        0b00000110, // digit 6
        0b00000111, // digit 7
        0b00001000, // digit 8
        0b00001001  // digit 9
    };

int main()
{
    if (ioperm(DATA_PORT, 1, 1))
    {
        fprintf(stderr, "Access denied to %x\n", DATA_PORT);
        exit(1);
    }

    while (1)
    {
        for (int digit = 0; digit < 10; digit++)
        {
            data = BCD_values[digit]; // Get BCD value for current digit
            outb(data, DATA_PORT);      // Display the digit
            sleep(1);                    // Delay for 1 second
        }
    }

    ioperm(DATA_PORT, 1, 0); // release the port
    return 0;
}