Question

atmega88 给OCR1A赋值时需要关闭中断吗

atmega88 给OCR1A赋值时需要关闭中断吗

Answer 1

//包含所需头文件
#include <ioM8v.h>
#include <macros.h>

/*------宏定义------*/
#define uchar unsigned char
#define uint unsigned int

//端口初始化
void port_init(void)
{
PORTB = 0x00;
DDRB = 0x00;
PORTC = 0x00;
DDRC = 0x00;
PORTD = 0x00;
DDRD = 0x00;
}

//定时T1初始化
void timer1_init(void)
{
TCCR1B = 0x00;//停止定时器
TIMSK |= 0x24;//中断允许
TCNT1H = 0xE1;
TCNT1L = 0x7B;//初始值
OCR1AH = 0xE0;
OCR1AL = 0xFF;//匹配A值
OCR1BH = 0xE0;
OCR1BL = 0xFF;//匹配B值
ICR1H = 0xFF;
ICR1L = 0xFF;//输入捕捉匹配值
TCCR1A = 0x00;
TCCR1B = 0x85;//启动定时器
}

//定时器T1输入捕捉中断服务程序
#pragma interrupt_handler timer1_capt_isr:6
void timer1_capt_isr(void)
{
//timer 1 input capture event, read (int)value in ICR1 using;
// value=ICR1L; //Read low byte first (important)
// value|=(int)ICR1H << 8; //Read high byte and shift into top byte
// TIFR|=BIT(ICF1);//软件写1清中断标志
}

//定时器T1溢出中断服务程序
#pragma interrupt_handler timer1_ovf_isr:9
void timer1_ovf_isr(void)
{
TCNT1H = 0xE1; //重装值高位
TCNT1L = 0x7B; //重装值低位
}

void init_devices(void)
{
CLI(); //禁止所有中断
MCUCR = 0x00;
MCUCSR = 0x80;//禁止JTAG
GICR = 0x00;
port_init();
timer1_init();
SEI();//开全局中断
}
//主函数
void main(void)
{
init_devices();
//在这继续添加你的代码
while(1)
{
NOP();
}
}