/*********************************************
File name	    : demo_6_5.c
Chip type           : ATmega16
Program type        : Application
Clock frequency     : 4.000000 MHz
Memory model        : Small
External SRAM size  : 0
Data Stack size     : 256
*********************************************/

// CodeVisionAVR C Compiler
// (C) 1998-2001 Pavel Haiduc, HP InfoTech S.R.L.

// I/O registers definitions for the ATmega16


#pragma used+
sfrb TWBR=0;
sfrb TWSR=1;
sfrb TWAR=2;
sfrb TWDR=3;
sfrb ADCL=4;
sfrb ADCH=5;
sfrw ADCW=4;      // 16 bit access
sfrb ADCSRA=6;
sfrb ADMUX=7;
sfrb ACSR=8;
sfrb UBRRL=9;
sfrb UCSRB=0xa;
sfrb UCSRA=0xb;
sfrb UDR=0xc;
sfrb SPCR=0xd;
sfrb SPSR=0xe;
sfrb SPDR=0xf;
sfrb PIND=0x10;
sfrb DDRD=0x11;
sfrb PORTD=0x12;
sfrb PINC=0x13;
sfrb DDRC=0x14;
sfrb PORTC=0x15;
sfrb PINB=0x16;
sfrb DDRB=0x17;
sfrb PORTB=0x18;
sfrb PINA=0x19;
sfrb DDRA=0x1a;
sfrb PORTA=0x1b;
sfrb EECR=0x1c;
sfrb EEDR=0x1d;
sfrb EEARL=0x1e;
sfrb EEARH=0x1f;
sfrw EEAR=0x1e;   // 16 bit access
sfrb UBRRH=0x20;
sfrb UCSRC=0X20;
sfrb WDTCR=0x21;
sfrb ASSR=0x22;
sfrb OCR2=0x23;
sfrb TCNT2=0x24;
sfrb TCCR2=0x25;
sfrb ICR1L=0x26;
sfrb ICR1H=0x27;
sfrb OCR1BL=0x28;
sfrb OCR1BH=0x29;
sfrw OCR1B=0x28;  // 16 bit access
sfrb OCR1AL=0x2a;
sfrb OCR1AH=0x2b;
sfrw OCR1A=0x2a;  // 16 bit access
sfrb TCNT1L=0x2c;
sfrb TCNT1H=0x2d;
sfrw TCNT1=0x2c;  // 16 bit access
sfrb TCCR1B=0x2e;
sfrb TCCR1A=0x2f;
sfrb SFIOR=0x30;
sfrb OSCCAL=0x31;
sfrb OCDR=0x31;
sfrb TCNT0=0x32;
sfrb TCCR0=0x33;
sfrb MCUCSR=0x34;
sfrb MCUCR=0x35;
sfrb TWCR=0x36;
sfrb SPMCR=0x37;
sfrb TIFR=0x38;
sfrb TIMSK=0x39;
sfrb GIFR=0x3a;
sfrb GICR=0x3b;
sfrb OCR0=0X3c;
sfrb SPL=0x3d;
sfrb SPH=0x3e;
sfrb SREG=0x3f;
#pragma used-

// Interrupt vectors definitions


// Needed by the power management functions (sleep.h)
#asm
	#ifndef __SLEEP_DEFINED__
	#define __SLEEP_DEFINED__
	.EQU __se_bit=0x40
	.EQU __sm_mask=0xB0
	.EQU __sm_powerdown=0x20
	.EQU __sm_powersave=0x30
	.EQU __sm_standby=0xA0
	.EQU __sm_ext_standby=0xB0
	.EQU __sm_adc_noise_red=0x10
	.SET power_ctrl_reg=mcucr
	#endif
#endasm


// CodeVisionAVR C Compiler
// (C) 1998-2000 Pavel Haiduc, HP InfoTech S.R.L.


#pragma used+

void delay_us(unsigned int n);
void delay_ms(unsigned int n);

#pragma used-


/**********************數碼管顯示相關宏定義*******************************/  
flash unsigned char  led_7[10]={0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90};   //共陽極數碼管
flash unsigned char  position[4]={0x80,0x40,0x20,0x10};    //位選               

unsigned char  time[3];				        // 時、分、秒計數
unsigned char  dis_buff[4];              // 顯示緩沖區，存放要顯示的4個字符的段碼值                                    				
unsigned char  time_counter;				// 1秒計數器
bit point_on;			                // 秒顯示標志

// 時間顯示函數，執行時間12ms
void time_display(void)				
{
	unsigned char  i;
 	for(i=0;i<=3;i++)
	{       
	        PORTD &= 0x0F;
		PORTC = led_7[dis_buff[i]]; 
		if (point_on && ( i==2)) PORTC &= 0x7F;	
		PORTD|= position[i]; 
       	        delay_ms(3);
       	        PORTD&=0X0F;																	
  	}
}

// 時間值送顯示緩沖區函數
void time_to_disbuffer(void)			
{
	unsigned char  i,j=0;
	for (i=1;i<=2;i++)
	{
		dis_buff[j++] = time[i] % 10;
		dis_buff[j++] = time[i] / 10;
	}
}

/**********************MCU初始化*******************************/
void mcu_init(void)
{
        DDRA=0X1D;  //00011101 
        DDRB=0XB1;  //10110001
        PORTB=0X00;
        DDRC=0XFF;
        PORTC=0XFF;
        DDRD=0XF0;
        PORTD=0X00;
} 

/**********************主函數*******************************/  
void main()
{
        mcu_init();
        time[2] = 23; time[1] = 58; time[0] = 55;	// 時間初值23:58:55
        time_to_disbuffer();
        
         while (1)
       {
	    time_display();						// 顯示掃描，執行時間12ms
	    if (++time_counter >= 40)
	    {
		    time_counter = 0;				
		    point_on = ~point_on;			
		    if (++time[0] >= 60)
		    {
			    time[0] = 0;                        
			    if (++time[1] >= 60)
			    {
				    time[1] = 0;
				    if (++time[2] >= 24) time[2] = 0;   
			    }
		    } 
	       time_to_disbuffer();
	    }            
           delay_ms(13);
      } 
}