说明：  PWM 码是一种脉宽调制码，它的组成为9MS 高电 平和4MS 低电平引导脉冲，16 位系统识别码 正码和8 位数据反码。我们要解的就数据码。一个PWM 码的0是由一个0.58ms的低电平和一个0.58ms的高电平
(code is a PWM pulse width modulation code, which is composed of 9MS to I and decent low-level guide pulse, sixteen system identification code and the code is data-8 yards. We have to be resolved on the data codes. A PWM yards from the zero is a low-level 0.58ms and a 0.58ms allow high output)