微秒级延时函数
正常用的延时函数精准度太低了，现在提供两种延时，一种是c++ chrono新特性来实现的，一种是windows时钟实现的。
chrono实现
#include <chrono>
void timeUsC(int iTimeUs)
{
auto start = std::chrono::system_clock::now();
while (true)
{
auto end = std::chrono::system_clock::now();
auto duration = std::chrono::duration_cast<std::chrono::microseconds>(end - start);
if (duration.count() > iTimeUs)
{
break;
}
}
}
windows时钟实现
#include <windwos.h>
int timeUsWindows(int us)
{
LARGE_INTEGER fre;
if (QueryPerformanceFrequency(&fre)) //判断是否支持
{
LARGE_INTEGER run, priv, curr;
run.QuadPart = fre.QuadPart * us / 1000000;
QueryPerformanceCounter(&priv); //获取当前的
do
{
QueryPerformanceCounter(&curr);
} while (curr.QuadPart - priv.QuadPart < run.QuadPart);
curr.QuadPart -= priv.QuadPart;
int nres = (curr.QuadPart * 1000000 / fre.QuadPart);
return nres;
}
return -1;
}
