#include <LPC17xx.h>
#include <stdlib.h>

#define RS_CTRL 0x08000000
#define EN_CTRL 0x10000000
#define DT_CTRL 0x07800000

unsigned long int temp1 = 0, temp2 = 0, i, j;
unsigned char flag1 = 0, flag2 = 0;
unsigned char msg[] = ("Dice: ");

void lcd_write(void);
void port_write(void);
void delay_lcd(unsigned long);

unsigned long int init_command[] = {0x30,0x30,0x30,0x20,0x28,0x0C,0x01,0x80};

int main() {
    LPC_GPIO0->FIODIR = DT_CTRL | RS_CTRL | EN_CTRL;
    for (i = 0; i < 8; i++) { temp1 = init_command[i]; flag1 = 0; lcd_write(); }
    LPC_PINCON->PINSEL3 = 0; LPC_GPIO0->FIODIR &= ~(1 << 21);

    while (1) {
        while ((LPC_GPIO0->FIOPIN & (1 << 21)) != 0);
        flag1 = 0; temp1 = 0x01; lcd_write(); temp1 = 0x80; lcd_write();
        flag1 = 1; for (i = 0; msg[i] != '\0'; i++) { temp1 = msg[i]; lcd_write(); }
        j = (rand() % 6) + 1; temp1 = '0' + j; lcd_write();
        while ((LPC_GPIO0->FIOPIN & (1 << 21)) == 0);
    }
}

void lcd_write(void) {
    flag2 = (flag1 == 1) ? 0 : (((temp1 == 0x30) || (temp1 == 0x20)) ? 1 : 0);
    temp2 = (temp1 & 0xF0) << 19; port_write();
    if (!flag2) { temp2 = (temp1 & 0x0F) << 23; port_write(); }
}

void port_write(void) {
    LPC_GPIO0->FIOPIN = temp2;
    if (flag1 == 0) LPC_GPIO0->FIOCLR = RS_CTRL; else LPC_GPIO0->FIOSET = RS_CTRL;
    LPC_GPIO0->FIOSET = EN_CTRL; delay_lcd(100); LPC_GPIO0->FIOCLR = EN_CTRL;
    delay_lcd(500000);
}

void delay_lcd(unsigned long r1) { unsigned long r; for (r = 0; r < r1; r++); }