这是我自己编写的三分频，也就是奇数分频，占空比为1：1，当然如果需要其它奇数分频，只要将程序里面的N和counter修改即可-This was my third prepared by the frequency, which is odd hours, frequency and duty ratio of 1:1. Of course, if the needs of other odd hours, frequency, as long as the proceedings inside the N and counter can be amended