作者wayneshiau (Wayne)
看板Grad-ProbAsk
标题[理工] Register与Memory Size问题
时间Sat Apr 20 12:04:22 2019
今天看到一题如下，请问要如何计算？
If the computer has 32 data registers (R0 to R31), 2000 words in memory,
and 16 different instructions. What is the minimum size of an add instruction
in bits if a typical instruction use the following format: add R0 R2
(A) 14
(B) 13
(C) 28
(D) 29
答案是给A 请问是如何得出的？
感谢各位！
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1F：推 skyHuan: 16 instrs. => op code要4码 04/20 12:14
2F：→ skyHuan: 32 regs => rs/rt要5码 04/20 12:14
3F：→ skyHuan: 所以此type的指令需要4+5+5=14码 04/20 12:14