计数器竞争冒险及其处理的仿真分析  

The simulation analysis of counter competition risk and its processing

作　　者：司佑全[1] 张学文[1] 

机构地区：[1]湖北师范学院物理与电子科学学院,湖北黄石435002

出　　处：《湖北师范学院学报（自然科学版）》2015年第1期25-28,共4页Journal of Hubei Normal University(Natural Science)

基　　金：湖北师范学院教研项目(JH201129;ZD201121)

摘　　要：采用同步清零或置数方式完成的计数器,一般不会出现竞争冒险现象,而采用异步清零或置数方式完成的计数器往往会出现竞争冒险现象。以74LS160同步计数器(异步复位、同步置数)组成的7进制计数器为例,利用multisim仿真软件来进行分析,并且给出消除异步复位产生的竞争冒险的方法。结果表明采用延时法和异步清零、异步置数变成同步清零、同步置数法,可以有效地消除计数器采取异步清零、异步置数方式所产生的竞争冒险,使得计数器能正常工作。In general, won ＇t appear competitive adventure phenomenon in counter adopting the synchronous reset or several way, but for counter adopting the asynchronous reset or several way, will often appear competitive adventure phenomenon. In this paper, taking 74LS160 synchronous counter （sync） composed of seven binary counter as an example, the authors analysis that problems using the multisim simulation software, and provide a method to eliminate the asynchronous reset the competition adventure. The study show that the time delay method as well as is synchronization method adopted and asynchronous reset, asynchronous load into the synchronous reset, can effectively eliminate competition risk appearing in the counter taking the asynchronous reset, asynchronous several ways, which can assure the counter normally work.

关 键 词：MULTISIM 虚拟仿真 竞争冒险 计数器 异步 同步 

分 类 号：TP302.2[自动化与计算机技术—计算机系统结构]