在开发过程中，通常要进行时钟可靠性测试，主要有相位的变化　、占空比的变化。本代码实现了时钟相位变化和占空比的变化。-In the development process, usually the reliability of the test clock, there are phase changes, the duty cycle changes. Implementation of the code phase of the clock change and the duty cycle changes.