// File Name : main.c
// Programmed by Jimmy Seo
// Program Date : Mon., May 10, 2004
//
#include <GC80C520_PL44I.H>
#include "timer.h"

// Declaration of the Variables
xdata unsigned char *pcode;				  // for External Memory
data unsigned char  temp1;				  // for Temporary Data
data unsigned char  temp;				  
data unsigned char  i;					  // for Loop Parameters
data unsigned char  p;					  // for Loop Parameters
data unsigned char	port_change;		  // for PORT Display Delection
data unsigned char	port_value_change;	  // for PORT Value Update Change
data unsigned char	port_display_change;  // for PORT Display Selection

unsigned int	loop_cnt;			// for Loop Parameter    @ timer0
unsigned char	display_count;		// for Display Parameter @timer0


// Prototype Functions
// 1. System Initialization
void initialize(void);

// 2. Led Output
//void output_led(void);


// Sub Function : 8.  void msec(int) {
/* delay function for m seconds */
void msec(int Delay)
{
	int i, j;
	for(j=0; j<Delay; j++)
		for (i=0; i<100; i++);
}



// Sub Function : 9.  void delay_lcd(unsigned int) {
void delay_lcd(unsigned int t) {

//	unsigned int i;
	for(i=0; i<t; i++);
}


// 3. delay fuction
//void delay (int);
// Sub Function - 1. void initialize_lcd(void)
void initialize_lcd(void) {


	pcode = (unsigned char xdata *)0xF200;
	*(pcode) = 0x00;		// LCD_RW = 0;
	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x00;		// LCD_EN = 0;
	pcode = (unsigned char xdata *)0xF000;
	*(pcode) = 0x00;		// LCD_RS = 0;

	msec(15);
	msec(15);
	msec(15);


	pcode = (unsigned char xdata *)0xF300;
	*(pcode) = FUNCTION_SET2;
	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x01;		// LCD_EN = 1;
	*(pcode) = 0x00;		// LCD_EN = 0;

	msec(5);
	msec(5);
	msec(5);
	
	pcode = (unsigned char xdata *)0xF300;
	*(pcode) = FUNCTION_SET2;
	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x01;		// LCD_EN = 1;
	*(pcode) = 0x00;		// LCD_EN = 0;

	msec(2);
	msec(2);
	msec(2);
	
	pcode = (unsigned char xdata *)0xF300;
	*(pcode) = FUNCTION_SET2;
	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x01;		// LCD_EN = 1;
	*(pcode) = 0x00;		// LCD_EN = 0;

	msec(1);
	msec(1);
	msec(1);
	
	pcode = (unsigned char xdata *)0xF300;
	*(pcode) = FUNCTION_SET2;
	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x01;		// LCD_EN = 1;
	*(pcode) = 0x00;		// LCD_EN = 0;

	delay_lcd(45);
	delay_lcd(45);
	delay_lcd(45);


	pcode = (unsigned char xdata *)0xF300;
	*(pcode) = DISPLAY_ON1;
	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x01;		// LCD_EN = 1;
	*(pcode) = 0x00;		// LCD_EN = 0;

	delay_lcd(255);
	delay_lcd(255);
	delay_lcd(255);


	pcode = (unsigned char xdata *)0xF300;
	*(pcode) = CLEAR_DISPLAY1;
	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x01;		// LCD_EN = 1;
	*(pcode) = 0x00;		// LCD_EN = 0;

	delay_lcd(255);
	delay_lcd(255);
	delay_lcd(255);


	pcode = (unsigned char xdata *)0xF300;
	*(pcode) = ENTRY_MODE1;
	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x01;		// LCD_EN = 1;
	*(pcode) = 0x00;		// LCD_EN = 0;

	delay_lcd(255);
	delay_lcd(255);
	delay_lcd(255);


	pcode = (unsigned char xdata *)0xF000;
	*(pcode) = 0x01;		// LCD_RS = 1;
	
	msec(1);
	msec(1);
	msec(1);

} // End: void initialize_lcd(void)




// Sub Function - 2. void clearscreen_lcd(void)
void clearscreen_lcd(void) {
	// pcode = 0xFFXX : PORTA (and Character LCD Display Databus)
	// pcode = 0xF9XX : LCD_CON[0] (LCD_RW)
	// pcode = 0xF8XX : LCD_CON[1] (LCD_EN)
	// pcode = 0xF7XX : LCD_CON[2] (LCD_RS)

	pcode = (unsigned char xdata *)0xF000;
	*(pcode) = 0x00;		// LCD_RS = 0;

	pcode = (unsigned char xdata *)0xF300;
	*(pcode) = CLEAR_DISPLAY1;
	
	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x01;		// LCD_EN = 1;
	*(pcode) = 0x00;		// LCD_EN = 0;

	pcode = (unsigned char xdata *)0xF000;
	*(pcode) = 0x01;		// LCD_RS = 1;

	delay_lcd(255);
	delay_lcd(255);
	delay_lcd(255);
} // End: void clearscreen_lcd(void)



// Main Function
//
void main(void) {

	initialize();
	initialize_lcd();

	clearscreen_lcd();	

	
	loop_cnt = 0;

	TR0 = 1;	// Timer0 Start (Enable)

	
	while(1){
		temp = 0;
	}

	
} // End: void Main(void)




// Sub Function - 1. void initialize(void)
void initialize(void) {
	TMOD  = 0x22; 	// Timer 0/1 : Mode 2<Auto Reload>
					
    
	TH0   = 0x06;   // TH0 for Auto-reload
					// (Fosc/12)^-1*(256-TH0) = Timing Duty
					// When Fosc = 12MHz and TH0 = 0x06,
					// Timing Duty is 0.25msec (250 usec)
		
	pcode = (unsigned char xdata *)0x0000;

	ET0 = 1;		// Timer 0 Interrupt Enable
	EA =  1;		// All Interrupts Enable
	
	display_count = 0;
	loop_cnt = 0;

} // End: void initialize(void)

void print_char_lcd(unsigned char c) {
	// pcode = 0xFFXX : PORTA (and Character LCD Display Databus)
	// pcode = 0xF9XX : LCD_CON[0] (LCD_RW)
	// pcode = 0xF8XX : LCD_CON[1] (LCD_EN)
	// pcode = 0xF7XX : LCD_CON[2] (LCD_RS)

	pcode = (unsigned char xdata *)0xF000;
	*(pcode) = 0x01;		// LCD_RS = 1;

	pcode = (unsigned char xdata *)0xF300;
	*(pcode) = c;
	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x01;		// LCD_EN = 1;
	*(pcode) = 0x00;		// LCD_EN = 0;

	pcode = (unsigned char xdata *)0xF000;
	*(pcode) = 0x00;		// LCD_RS = 0;

	
	delay_lcd(45);
	
	
} // End: void print_char_lcd(BYTE c)


// Sub Function : 6. void print_string_lcd(const char *)
void print_string_lcd(const char *s) {
	// pcode = 0xFFXX : PORTA (and Character LCD Display Databus)
	// pcode = 0xF9XX : LCD_CON[0] (LCD_RW)
	// pcode = 0xF8XX : LCD_CON[1] (LCD_EN)
	// pcode = 0xF7XX : LCD_CON[2] (LCD_RS)

	while (*s) {
		print_char_lcd(*s++);
	}

	delay_lcd(225);
	
} // End: void print_string_lcd(const char *s)

// Sub Function - 3. void address_lcd(BYTE)
void address_lcd(unsigned char addr) {
	// pcode = 0xFFXX : PORTA (and Character LCD Display Databus)
	// pcode = 0xF9XX : LCD_CON[0] (LCD_RW)
	// pcode = 0xF8XX : LCD_CON[1] (LCD_EN)
	// pcode = 0xF7XX : LCD_CON[2] (LCD_RS)
	
	pcode = (unsigned char xdata *)0xF000;
	*(pcode) = 0x00;		// LCD_RS = 0;

	pcode = (unsigned char xdata *)0xF300;
	*(pcode) = addr;

	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x01;		// LCD_EN = 1;
	*(pcode) = 0x00;		// LCD_EN = 0;

	pcode = (unsigned char xdata *)0xF000;
	*(pcode) = 0x01;		// LCD_RS = 1;

	delay_lcd(255);
	delay_lcd(255);
	delay_lcd(255);

} // End: void address_lcd(unsigned char addr) 

// Sub Function : 6.  void PutChar(unsigned char) {
void PutChar(unsigned char c) {
	pcode = (unsigned char xdata *)0xF000;
	*(pcode) = 0x01;		// LCD_RS = 1;

	pcode = (unsigned char xdata *)0xF300;
	*(pcode) = c;
	
	pcode = (unsigned char xdata *)0xF100;
	*(pcode) = 0x01;		// LCD_EN = 1;
	*(pcode) = 0x00;		// LCD_EN = 0;
	pcode = (unsigned char xdata *)0xF000;
	*(pcode) = 0x00;		// LCD_RS = 0;
	delay_lcd(45);
	delay_lcd(45);
	delay_lcd(45);
	delay_lcd(45);
}

/* Function to output the decimal value of the count on the LCD */
void Print_INT(unsigned short* d) {

	unsigned char hund,ten,one;
	unsigned char poly, temp;
	unsigned short value;

	value = *d;
	ten = value/10;
	one = (value-ten*10);

	for (poly = 0; poly < 2; poly++) {
		if (poly == 0) temp = ten;
		else temp = one;
		switch (temp) {
			case 0 : PutChar('0'); break;
			case 1 : PutChar('1'); break;
			case 2 : PutChar('2'); break;
			case 3 : PutChar('3'); break;
			case 4 : PutChar('4'); break;
			case 5 : PutChar('5'); break;
			case 6 : PutChar('6'); break;
			case 7 : PutChar('7'); break;
			case 8 : PutChar('8'); break;
			case 9 : PutChar('9'); break;
		}
	}

}


// Sub Function : Timer 0 Interrupt
void timer0_int(void) interrupt TF0_VECTOR {
	static int seconds;
	static unsigned short hour, min, sec;
	
	
	// 7-segment Display	
	if (loop_cnt == 4000) {	 // 2000 : 0.5sec
		seconds++;
		hour = seconds / 3600;
		min = (seconds - hour * 3600) / 60;
		sec = (seconds - hour * 3600 - min * 60);
		
		address_lcd(DDRAM_ADDR_EVEN);
		print_string_lcd("  Digital Clock");
		
		address_lcd(DDRAM_ADDR_EVEN+0x14);
		Print_INT(&hour);
		PutChar(':');
		Print_INT(&min);
		PutChar(':');		
		Print_INT(&sec);
		loop_cnt = 0;
		
		switch (display_count) {
			case 0 :
				pcode = (unsigned char xdata *) 0xF600;		// Port B (7-segment Display)
				*(pcode) = D0;		// Refer to timer.h file about MACRO "D0".
				display_count++;
				break;
			case 1 :
				pcode = (unsigned char xdata *) 0xF600;		// Port B (7-segment Display)
				*(pcode) = D1;		// Refer to timer.h file about MACRO "D0".
				display_count++;
				break;
			case 2 :
				pcode = (unsigned char xdata *) 0xF600;		// Port B (7-segment Display)
				*(pcode) = D2;		// Refer to timer.h file about MACRO "D0".
				display_count++;
				break;
			case 3 :
				pcode = (unsigned char xdata *) 0xF600;		// Port B (7-segment Display)
				*(pcode) = D3;		// Refer to timer.h file about MACRO "D0".
				display_count++;
				break;
			case 4 :
				pcode = (unsigned char xdata *) 0xF600;		// Port B (7-segment Display)
				*(pcode) = D4;		// Refer to timer.h file about MACRO "D0".
				display_count++;
				break;
			case 5 :
				pcode = (unsigned char xdata *) 0xF600;		// Port B (7-segment Display)
				*(pcode) = D5;		// Refer to timer.h file about MACRO "D0".
				display_count++;
				break;
			case 6 :
				pcode = (unsigned char xdata *) 0xF600;		// Port B (7-segment Display)
				*(pcode) = D6;		// Refer to timer.h file about MACRO "D0".
				display_count++;
				break;
			case 7 :
				pcode = (unsigned char xdata *) 0xF600;		// Port B (7-segment Display)
				*(pcode) = D7;		// Refer to timer.h file about MACRO "D0".
				display_count++;
				break;
			case 8 :
				pcode = (unsigned char xdata *) 0xF600;		// Port B (7-segment Display)
				*(pcode) = D8;		// Refer to timer.h file about MACRO "D0".
				display_count++;
				break;
			case 9 :
				pcode = (unsigned char xdata *) 0xF600;		// Port B (7-segment Display)
				*(pcode) = D9;		// Refer to timer.h file about MACRO "D0".
				display_count = 0;
				break;
			
		}
		
	}
	
	loop_cnt++;
	TF0 = 0;					 // Timer 0 Overflow Falg Clear

} // End : Sub Function - void timer0_int(void) interrupt TF0_VECTOR