说明：  电动车双闭环程序，采用双闭环方式控制电机，以得到最好的zh转速性能，并且可以 限制电机的最大电流。本应用程序用到两个CCP部件，其中CCP1用于PWM输出，以控 制电机电压；CCP2用于触发AD，定时器TMR2、TMR1，INT中断，RB口电平变化中断，
(Electric cars double-loop process, a dual closed-loop control of motors, zh to get the best speed performance, and may limit the maximum motor current. The application components used in the two CCP, of which CCP1 to PWM output to control the motor voltage CCP2 used to trigger AD, timer TMR2, TMR1, INT interrupt, RB port change interrupt level,)