基于集成移位寄存器的扭环形计数器自启动设计

摘要

Both state transition in twisted ring counters and logic function in shift registers are analyzed.Some new schemes for design of twisted ring counters based on shift register 74LS194 are purposed.State transition of shift registers is kept right shift or input numbers are accord with right shift rules,and the feedbacks carry out reverse circulation shift.Based on these rules,logic modification to the excitation function of any flip-flop could realize selfcorrection in twisted ring counters.The innovation of this method is that a logic modification method is proposed to change the application direction of MSI shift register.%分析了扭环形计数器工作时的状态转换过程,分析了集成移位寄存器的逻辑功能,提出了用集成移位寄存器74LS194构成扭环形计数器的一些新的设计方案,即移位寄存器的状态变化在右移移位或并行输入符合右移规律的数码、反馈实现取反循环移位的基础上,对任何一位触发器的激励函数进行逻辑修改,可实现扭环形计数器自启动设计.所述方法的创新点是提出了MSI集成移位寄存器改变应用方向的逻辑修改方法.