单周期和多周期数据路径之间的差异

1.单周期数据路径：
单个数据路径等效于原始的单周期数据路径。数据存储器只有一个地址输入。实际的存储器操作可以从MemRead和MemWrite控制信号中确定。有单独的指令和数据存储器。有2个用于基于PC的计算的加法器和一个ALU。控制信号是相同的。

2.多周期数据路径：
多周期数据路径将指令分解为单独的步骤。每个步骤占用一个时钟周期，每个功能单元在一条指令中可以使用多次，只要在不同的时钟周期中使用它即可。它减少了所需的硬件数量。它减少了平均教学时间。

单周期和多周期数据路径之间的区别：

S.No.	Single Cycle Datapath	Multiple Cycle Datapath
1	Instructions are not subdivided.	Instructions are divided into artitoray number of steps.
2	Clock cycles are long enough for the lowest instruction.	Clock cycles are short but long enough for the lowest instruction.
3	There are only 1 instruction that can be executed at the same time.	There are only 1 instruction that can be executed at the same time.
4	There is 1 cycle per instruction, i, e., CPI = 1.	There is a variable number of clock cycles per instructions.
5	Control unit generates signals for the entire instruction.	Control unit generates signals for the instruction’s current step and keeps track of the current step.
6	There is duplicate hardware, because we can use a functional unit for at most one subtask per instruction.	There is no duplicate hardware, because the instructions generally are broken into single FU steps.
7	Extra registers are not required.	Extra registers are required to hold the result of one step for use in the next step.
8	Performance is baseline.	Performance is slightly slower to mederaletly faster than single cycle, latter when the instructions steps are well balanced and a significantly fractions of the instructions take less than the maximum number of cycles.