计数器用一个开关K控制，当K=1时，可逆加法计数器进行计数，K=0时可逆减法计数器进行计数，即可构成一个具有清零和预置功能的可逆加减法计数器-counter with a control switch K, K = 1, the reversible addition counter for counting, K = 0 reversible subtraction counter for counting, with constitutes a reset and preset functi

一个最基础的23进制减法计数器，与加法想类似！-One of the most 23 hexadecimal subtraction based counters, and would like to add a similar!

Example3 加/减法计数器 本例程实现的是一个加/减8 进制计数器。其中包括时钟输入、使能信号、加减控制信 号、复位信号、三位输入和一位进位位。 -Example3 add/subtract counter implementation of this routine is a plus/minus 8 binary counter. These include the clock input enable signal, addition and subtractio

多功能计数器，能实现加法，减法，复位，装载的功能-Multi-function counter that can achieve the addition, subtraction, reset, load the function