The division operation is not frequent relatively in traditional applications, but it is increasingly indispensable and important in many modern applications. In this paper, the implementation of modified signed-digit...The division operation is not frequent relatively in traditional applications, but it is increasingly indispensable and important in many modern applications. In this paper, the implementation of modified signed-digit （MSD） floating-point division using Newton-Raphson method on the system of ternary optical computer （TOC） is studied. Since the addition of MSD floating-point is carry-free and the digit width of the system of TOC is large, it is easy to deal with the enough wide data and transform the division operation into multiplication and addition operations. And using data scan and truncation the problem of digits expansion is effectively solved in the range of error limit. The division gets the good results and the efficiency is high. The instance of MSD floating-point division shows that the method is feasible.展开更多
针对三值光学计算机(ternary optical computer,TOC)中可变位数改良符号数字(modified signed digit,MSD)加法器所面临的移位效率问题,提出了一种全新的数据移位方式,并设计了相应的可变距离移位寄存器.该移位方式为寄存器每个位的输入...针对三值光学计算机(ternary optical computer,TOC)中可变位数改良符号数字(modified signed digit,MSD)加法器所面临的移位效率问题,提出了一种全新的数据移位方式,并设计了相应的可变距离移位寄存器.该移位方式为寄存器每个位的输入线和输出线分别设置了对应数据总线不同位线的跨接旁路,每个旁路的电子开关由一位锁存器控制,通过给锁存器赋值来改变移位的距离,从而实现指定距离的快速移位,解决了当前移位寄存器因采用D触发器(D flip-flop,DFF)串连结构只能实现逐位移动而效率低下的问题.讨论了该新型移位技术的原理和可变距离移位寄存器的实现方案,给出了6个可变距离移位寄存器实例,并将这些实例与传统移位寄存器进行了对比实验.研究结果表明,该新型移位技术在时钟频率、移位延迟、硬件资源消耗和功耗方面明显优于传统移位技术,能够显著提升三值光学计算机中MSD加法器的性能.展开更多
基金Project supported by the Shanghai Leading Academic Discipline Project(Grant No.J50103)the National Natural Science Foundation of China(Grant No.61073049)
文摘The division operation is not frequent relatively in traditional applications, but it is increasingly indispensable and important in many modern applications. In this paper, the implementation of modified signed-digit （MSD） floating-point division using Newton-Raphson method on the system of ternary optical computer （TOC） is studied. Since the addition of MSD floating-point is carry-free and the digit width of the system of TOC is large, it is easy to deal with the enough wide data and transform the division operation into multiplication and addition operations. And using data scan and truncation the problem of digits expansion is effectively solved in the range of error limit. The division gets the good results and the efficiency is high. The instance of MSD floating-point division shows that the method is feasible.
