Computertechnik mit Mikrocontrollern

KAPITEL 13. AUFBAU DES SYSTEMS 189
#define tas2_PB PC4
#define tas3_DDR DDRC
#define tas3_PORT PORTC
#define tas3_PIN PINC
#define tas3_PB PC3
#define tas4_DDR DDRC
#define tas4_PORT PORTC
#define tas4_PIN PINC
#define tas4_PB PC2
#define taster_init() cbi (tas2_DDR,tas2_PB);\
sbi (tas2_PORT,tas2_PB);\
cbi (tas3_DDR,tas3_PB);\
sbi (tas3_PORT,tas3_PB);\
cbi (tas4_DDR,tas4_PB);\
sbi (tas4_PORT,tas4_PB);
void taster ()
{
if ( bit_is_clear(tas4_PIN, tas4_PB) ) uhr.second = uhr.nanosec = 0;;
if ( bit_is_clear(tas3_PIN, tas3_PB) && ! uhr.nanosec ) uhr.minute++;
if ( bit_is_clear(tas2_PIN, tas2_PB) && ! uhr.nanosec ) uhr.hour++;
}
#define Displen 16
char Disp0[Displen+3] = { "\f** Clock **\n" };
char Disp [Displen+2] = { "\r HH:MM:SS " };
// 01234567890123456 78
void displa (unsigned char i1, unsigned char i2)
{Disp[i1++]=i2/10+’0’; Disp[i1]=i2%10+’0’;}
void display()
{
static unsigned char lastval;
if (uhr.nanosec < lastval ) // saves 1 mA
{
displa (5,uhr.hour);
displa (8,uhr.minute);
displa (11,uhr.second);
putstring (Disp);
}
lastval = uhr.nanosec;
}
ISR ( SIG_OVERFLOW0 ) // timer0
{
sei();
TCNT0=CLOCKCNT0;
quarzuhr ();
taster ();
display ();
}