#include #include #define uchar unsigned char #define uint unsigned int void main() { DDRA=0X00; DDRB=0XFF; DDRD|=0X30; TCCR1A=0x91; //8位相位修正PWM 8000000/(64*2*256)=244.14hz TCCR1B=0x03; //clk/64 OCR1A=250; //初值占空比100%