正弦波._c

AVR之ATMega16

//外部晶振 8M
#include <ioM16v.h>
#include <macros.h>
#include"delay.h"



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

char x=0;
char auc_SinParam[128]={
128,134,140,147,153,159,165,171,177,182,188,193,198,204,208,213,
218,222,226,230,233,237,240,242,245,247,249,251,252,253,254,254,
254,254,253,252,251,250,248,246,244,241,238,235,232,228,224,220,
215,211,206,201,196,191,185,179,174,168,162,156,150,144,137,131,
125,119,112,106,100,94,88,82,77,71,65,60,55,50,45,41,
36,32,28,24,21,18,15,12,10,8,6,5,4,3,2,2,
2,2,3,4,5,7,9,11,14,16,19,23,26,30,34,38,
43,48,52,57,63,68,74,79,85,91,97,103,109,116,122,128 
};//128点正弦波样本值

//端口初始化
void port_init(void)
{
 PORTA = 0x00;//设置端口方向和数据
 DDRA  = 0x00;
 PORTB = 0x00;
 DDRB  = 0x00;
 PORTC = 0x00;
 DDRC  = 0x00;
 PORTD = 0x00;
 DDRD  = 0x20;
}


//定时T1初始化
void timer1_init(void)
{
 TCCR1B = 0x00;//停止定时器
 TIMSK |= 0x04;//中断允许
 TIFR   = 0x00;//中断标志位
 TCNT1H = 0x00;
 TCNT1L = 0x00;//初始值
 OCR1AH = 0x00;
 OCR1AL = 0xD0;//匹配A值
 OCR1BH = 0x00;
 OCR1BL = 0x7F;//匹配B值
 ICR1H  = 0xFF;
 ICR1L  = 0xFF;//输入捕捉匹配值
 TCCR1A = 0x81;
 TCCR1B = 0x09;//启动定时器
}


//定时器T1溢出中断服务程序
#pragma interrupt_handler timer1_ovf_isr:9
void timer1_ovf_isr(void)
{
 x=x+1;
 if (x>128)
 x=0;
 OCR1A=auc_SinParam[x];//auc_SinParam[x];取样点指针到比较匹配寄存器
}


void init_devices(void)
{
 CLI(); //禁止所有中断
 MCUCR  = 0x00;//INT0、INT1中断触发方式
 MCUCSR = 0x80;//禁止JTAG
 GICR   = 0x00;//外部中断使能
 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();
 }
}