说明：  c8051F120一个应用程序，测量输入信号的幅值，和频率，其中设计AD，CP0，交叉开关，系统时钟等的应用。
(c8051F120 an application, measurement of the input signal amplitude, and frequency, of which the design of AD, CP0, cross switches, such as the application of the system clock.)