stc15单片机硬件精准延时，递归，51单片机延时

最近做项目，写了一个硬件延时代码，喜欢的朋友请拷贝，评论一下，让我高兴一下好不

/*---------------------------------------------------------------------*/
/* --- STC MCU Limited ------------------------------------------------*/
/* --- STC 1T Series MCU Demo Programme -------------------------------*/
/* --- Mobile: (86)13922805190 ----------------------------------------*/
/* --- Fax: 86-0513-55012956,55012947,55012969 -----------------------*/
/* --- Tel: 86-0513-55012928,55012929,55012966 ------------------------*/
/* --- Web: www.STCMCU.com --------------------------------------------*/
/* --- Web: www.GXWMCU.com --------------------------------------------*/
/* --- QQ:  800003751 -------------------------------------------------*/
/* 如果要在程序中使用此代码,请在程序中注明使用了STC的资料及程序        */
/*---------------------------------------------------------------------*/


#include "stc15wxx.h"
#include "main.h"
#include "pwm.h"

#define Timer0_Rate_HZ     (1000000)       //中断频率,最小频率 FOSC/Timer0_Rate_HZ=65536,最大FOSC/Timer0_Rate_HZ=1
#if (Timer0_Rate_HZ >FOSC)
#error "Timer0_Rate_HZ > FOSC !!!"
#endif
#define Timer0_Reload   (65536UL -( FOSC/ Timer0_Rate_HZ))        //Timer 0 重装值
/**********************************************/
u8  flag;
void time0_init(void)
{
    AUXR |=  (1<<7);    // Timer0 set as 1T mode
    TMOD &= ~(1<<2);    // Timer0 set as Timer
    TMOD &= ~0x03;      // Timer0 set as 16 bits Auto Reload
    TH0 = 0 / 256;  //Timer0 Load
    TL0 = 0 % 256;
    ET0 = 0;        //Timer0 Interrupt Disable
    PT0 = 0;        //高优先级
    TR0 = 0;        //Timer0 not Run
    EA = 1;         //打开总中断

}
void timer0 (void) interrupt 1
{
    flag = 0;
    ET0 = 0;
    TR0 = 0;
}

void timer_load(u16 load)
{
    flag = 1;
    TH0 = load / 256;  //Timer0 Load
    TL0 = load % 256;
    ET0 = 1;
    TR0 = 1;
    while(flag);
}
//递归延时函数
#define F_MHZ (24) //定义时钟是多少M
void Hdelay_nus(u16 nus)
{
    if(nus<=(65536/F_MHZ))
    {
        timer_load(65536UL-F_MHZ*nus);
        return;
    }
    else
    {
        timer_load(65536%F_MHZ);//接近16位定时最大延时
        nus -= (65536/F_MHZ);
        Hdelay_nus(nus);
    }
}

void Hdelay_nms(u16 nms)
{
    while(nms--)
    {
        Hdelay_nus(1000-1);
    }
}