#define BUSY 0x80

#define LCD_command_write 0x0000
#define LCD_data_write 0x0001
#define LCD_command_read 0x0002
#define LCD_data_read 0x0003

#define LCD 0x0A

LcdReady()
{
        char flag;
        while((flag=xpeek(LCD,LCD_command_read) & BUSY))  
	{
		if(flag == 0xFF) return -1;  
	}
	return 1;
}

void clr_screen(void)       
{
	LcdReady();
        xpoke(LCD,LCD_command_write,0x01);
}


char InitLcd(void)
{
	if(-1 ==LcdReady()) return -1;
        xpoke(LCD,LCD_command_write,0x38);

	LcdReady();
        xpoke(LCD,LCD_command_write,0x0c);
        clr_screen();
        goto_xy(0,0);
}

goto_xy(char x,char y)
{
    LcdReady();
    switch(y){
        case 0 : xpoke(LCD,LCD_command_write,(0x80+x)); break;
        case 1 : xpoke(LCD,LCD_command_write,(0xC0+x)); break;
        case 2 : xpoke(LCD,LCD_command_write,(0x94+x)); break;
        case 3 : xpoke(LCD,LCD_command_write,(0xd4+x)); break;
    }
}

char *Puts(char* str)
{
	unsigned char i;

	for (i=0; str[i] != '\0'; i++){
		LcdReady();
                xpoke(LCD,LCD_data_write,str[i]);
	}
	return str;
}

void putch_lcd(char ch)
{
	LcdReady();
        xpoke(LCD,LCD_data_write,ch);
}

// print 4 digits decimal on LCD at current position

print_4digit(int n)
{
       char buffer[6];
       int temp;

       if(n<0) buffer[0] = '-';
        else buffer[0] = '+';
        temp = n;
       if(n<0)
       {
        n=~temp;
        n++; // convert to unsigned
        }

    buffer[1] = (n/1000)+48;
    temp = n%1000;
    buffer[2] = (temp/100)+48;
    temp = n%100;
    buffer[3] = (temp/10)+48;
    buffer[4] = (temp%10)+48;
    putch_lcd(buffer[0]);
    putch_lcd(buffer[1]);
    putch_lcd(buffer[2]);
    putch_lcd(buffer[3]);
    putch_lcd(buffer[4]);
}