详细描述n比特计数器及RTL验证，计数器的位宽用generic语句设置为参数。MY_CNTR是一个n比特二进制的计数器，可以向上向下计数，并可设置计数值，计数器用异步的方式进行低电平复-A detailed descr iption of n-bit counter and RTL verification, the bit counter is set to use generic parameters statement. MY_CNTR is an n-bit binary counter, counting down to up, and set of values, counters with asynchronous low-level approach to rehabilitation