위치제어

#include <avr/io.h>
#include <avr/interrupt.h>
#define F_CPU 16000000UL
#include <util/delay.h>
#include <stdio.h>

const char Segment_Data[ 10 ]   = { 0x3F, 0x06, 0x5B, 0x4F, 0x66, 0x6D, 0x7D, 0x27, 0x7F, 0x67 };
unsigned char Display_Num[ 4 ]  = { 0, 0, 0, 0 };   // Seven segment 4자리 숫자 출력 버퍼
unsigned char Digit_Num         = 0;
unsigned char Begin             = 1;
unsigned char Direction         = 0;
unsigned long Gap               = 0;
long Count                      = 5000;


void Init_Devices( void );
void Init_Port( void );
void Init_Timer0( void );
void Init_Timer2( void );
void Init_Ext( void );
void Display( int Num );
void Control( int Command, int Start );

int main( void )
{
    Init_Devices();
    while( 1 )
    {
        Control( 1000, 0x10 );
    }
    return 0;
}


ISR( TIMER0_OVF_vect )
{
    Digit_Num++;
    Digit_Num   = Digit_Num % 4;
    PORTA       = Segment_Data[ Display_Num[ Digit_Num ] ];
    PORTC       = ~( 1 << Digit_Num );
    PORTB       |= ( 1 << PORTB0 );

    TCNT0       = 0xE7;
}

ISR( TIMER2_OVF_vect )
{
    if( !Direction )
    PORTB   |= ( 1 << PORTB7 );
    else
    PORTB   |= ( 1 << PORTB6 );
}

ISR( TIMER2_COMP_vect )
{
    PORTB   &= ~( ( 1 << PORTB7 ) | ( 1 << PORTB6 ) );
}

ISR( INT0_vect )
{
    Count++;
}

ISR( INT1_vect )
{
    Count--;
}

//call this routine to initialize all peripherals
void Init_Devices( void )
{
    //stop errant interrupts until set up
    cli(); //disable all interrupts
    XMCRA   = 0x00; //external memory
    XMCRB   = 0x00; //external memory
    Init_Port();
    Init_Timer0();
    Init_Timer2();
    Init_Ext();

    MCUCR   = 0x00;
    // EICRA    = 0x00; //extended ext ints
    // EICRB    = 0x00; //extended ext ints
    // EIMSK    = 0x00;
    // TIMSK    = 0x00; //timer interrupt sources
    ETIMSK  = 0x00; //extended timer interrupt sources
    sei(); //re-enable interrupt
    //all peripherals are now initialized
}

void Init_Port( void )
{
    PORTA   = 0x00;
    DDRA    |= ( 1 << DDA7 ) | ( 1 << DDA6 ) | ( 1 << DDA5 ) | ( 1 << DDA4 ) | ( 1 << DDA3 ) | ( 1 << DDA2 ) | ( 1 << DDA1 ) | ( 1 << DDA0 );
    PORTB   = 0x00;
    DDRB    |= ( 1 << DDB7 ) | ( 1 << DDB6 );
    PORTC   = 0x00; //m103 output only
    DDRC    |= ( 1 << DDC3 ) | ( 1 << DDC2 ) | ( 1 << DDC1 ) | ( 1 << DDC0 );
    PORTD   = 0x00;
    DDRD    &= ~( ( 1 << DDD3 ) | ( 1 << DDD2 ) | ( 1 << DDD1 ) | ( 1 << DDD0 ) );
    PORTE   = 0x00;
    DDRE    = 0x00;
    PORTF   = 0x00;
    DDRF    = 0x00;
    PORTG   = 0x00;
    DDRG    |= ( 1 << DDG1 ) | ( 1 << DDG0 );
    DDRG    &= ~( ( 1 << DDG3 ) | ( 1 << DDG2 ) );
}

//TIMER0 initialize - prescale:64
// WGM: Normal
// desiired value: 100uSec
// actual value: 100.000usec (0.0%)
void Init_Timer0( void )
{
    TCCR0   = 0x00;
    // ASSR = 0x00;
    TCNT0   = 0xE7;
    // OCR0 = 0xE7;
    TCCR0   |= ( 1 << CS02 );
    TIMSK   |= ( 1 << TOIE0 );
}

void Init_Timer2( void )
{
    TCCR2   = 0x00; //stop
    // ASSR = 0x00; //set async mode
    // TCNT2    = 0x06; //set count
    OCR2    = 0x00;
    TCCR2   |= ( 1 << WGM20 );
    TCCR2   |= ( 1 << CS22 ); //start timer
    TIMSK   |= ( 1 << OCIE2 ) | ( 1 << TOIE2 );
}

void Init_Ext( void )
{
    EICRA   |= ( 1 << ISC10 ) | ( 1 << ISC00 );
    EICRB   = 0;
    EIMSK   |= ( 1 << INT1 ) | ( 1 << INT0 );
}

void Display( int Num )
{
    Display_Num[ 0 ]    = ( Num % 10000 ) / 1000;
    Display_Num[ 1 ]    = ( Num % 1000 ) / 100;
    Display_Num[ 2 ]    = ( Num % 100 ) / 10;
    Display_Num[ 3 ]    = ( Num % 10 );
}

void Control( int Command, int Start )
{
    if( Begin )
    {
        OCR2    = Start;
        Begin   = 0;
    }
    if( Command > Count )
    {
        Gap     = Command - Count;
        Direction = 0;
    }

    if( Command < Count )
    {
        Gap     = Count - Command;
        Direction = 1;
    }
    if( Gap > 3000 )
        OCR2 = 127;
    else if( Gap < 2000 )
        OCR2 = 100;
    else if( Gap < 1000 )
        OCR2 = 50;
    else if( Gap < 100 )
        OCR2 = 40;
    else if( Gap < 10 )
        OCR2 = 1;
    Display( Count );
}