本帖最后由 ghye 于 2011-5-11 14:32 编辑
代码如下：- #include <avr/io.h>
- #include <avr/interrupt.h>
- #define F_CPU 8000000UL
- #include <util/delay.h>
- unsigned short icp1_tmr1;
- unsigned short icp1_tmr2;
- unsigned short icp1_cnt;
- unsigned char icp1_ok;
- inline void gpio_init(void)
- {
- DDRA = 0x0f;//LED gpio
- DDRC = 0x00;
- PORTC =0x01;//接key1的PC0口输入，上拉有效
- DDRD = 0x00;
- PORTD =0x10;//接红外一体接收头的引脚为输入，上拉有效
- SFIOR = 0x00;//全局上拉使能。默认使能
- }
- inline int chk_key1(void)
- {
- if( !(PINC & 0x01))
- {
- _delay_ms(20);
- if( !(PINC &0x01))
- return 1;
- }
- return 0;
- }
- inline void icp1_init(void)
- {
- icp1_cnt = 0;
- }
- ISR(TIMER1_CAPT_vect)
- {
- if(icp1_cnt > 0)
- {
- TIMSK &= ~_BV(TICIE1); //使能T/C1输入捕捉中断。没定是否需要T/C1溢出中断
- PORTA = 0x02;//LED灯测试
- _delay_ms(1000);
- }
- else if(icp1_cnt == 0)
- {
- PORTA = ~PORTA;//LED灯测试
- icp1_tmr1 = ICR1;
- }
- icp1_cnt++;
- }
- int main(void)
- {
- gpio_init();
- TCCR1B = 0x01;//icp1下降沿输入触发捕捉，1分频 . T/C1正常计数方式
- sei();
- while(1)
- {
- if(chk_key1())
- {
- icp1_init();
- TIMSK |= _BV(TICIE1); //使能T/C1输入捕捉中断。没定是否需要T/C1溢出中断
- }
- }
- return 0;
- }
下载atmega128a板子上测试发现，一直运行：
else if(icp1_cnt == 0)
{
PORTA = ~PORTA;
icp1_tmr1 = ICR1;
}
而从来都没icp1_cnt > 0的情况。
为何下次捕捉中断时，icp1_cnt还是0呢？ 请指教
环境：
avr-gcc (GCC) 4.3.2
Copyright (C) 2008 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
| 
楼主
