AVR单片机定时器1输入捕获功能设计的频率计

#define F_CPU 1000000UL #include<avr/io.h> #include<util/delay.h> #include<avr/interrupt.h> #define uchar unsigned char #define uint unsigned int #define StartKey (PINC & _BV(PC0)) const uchar DsyCode[]= { 0x3F,0x06,0x5B,0x4F,0x66,0x6D,0x7D,0x07,0x7F,0x6F,0x00 }; uchar DsyBuffer[4]={0,0,0,0}; uint capi=0, capj=0; void Port_Init(void); void Timer_Init(void); void Smg_Display(void); int main(void) { Port_Init(); Timer_Init(); sei(); while(1) { if(StartKey == 0) { TCCR1B |= _BV(CS10); TIMSK |= _BV(TICIE1); } Smg_Display(); } } ISR(TIMER1_CAPT_vect) { if(capi == 0) capi = ICR1; else { capj = ICR1 - capi; capj = 1000000UL/capj; TIMSK = 0x00; TCCR1B &= 0xf8; DsyBuffer[0]=capj / 1000; DsyBuffer[1]=capj % 1000 / 100; DsyBuffer[2]=capj % 100 / 10; DsyBuffer[3]=capj % 10; TCNT1 = capi = capj = 0; } } void Port_Init(void) { DDRA = 0xff; PORTA = 0x00; DDRB = 0xff; PORTB = 0xff; DDRC = 0x00; PORTC = 0xff; DDRD = 0x00; PORTD = 0x00; } void Timer_Init(void) { TCCR1B |= _BV(ICNC1)|_BV(ICES1); } void Smg_Display(void) { uchar i; for(i=0; i<4; i++) { PORTB = ~(1 << i); PORTA = DsyCode[DsyBuffer[i]]; if(i==0) PORTA |= 0x80; _delay_ms(2); } }