high=921.6;HighRH = (unsigned char)(high>>8);这个值是多少?HighRL = (unsigned char) high; 这个值又是多少?懂行的解释下,这个程序是PWM LED灯逐渐变亮的过程,HighRH = (unsigned char)(high>>8) 书上注解,高电平的重载值拆分为高低字节,HighRL = (unsigned char) high;