Design:

Design an instruction set of a $16-$bit CPU that has only $16$ instructions.

Note that no two instructions in an instruction set can be identical.

The length of the machine code for each of the instructions should be

$16$ bits. The instructions should belong to at least three different

formats. Make and state any necessary assumptions. Explain all the

design decisions.

In addition to everything you would like to include in the report, make

sure to include a list of registers, instruction formats, explanation on

why you have selected certain instructions, which registers an instruction

uses, etc.

Following are some key points that could be followed when working on

the project.

Decide how many registers the CPU is going to have. Aim to maximize

the number of registers. $($We have $32$ registers in LEGv$8$ processor.$)$

Decide which instructions the CPU is going to have.

Decide which instruction format each of the instructions will use.

$($We have R$-$format, D$-$format, etc. for LEGv$8$ processor.$)$

Decide the opcode for each of the instructions. Decide how many

bits are necessary to represent the opcodes and each of the registers.

$($LEGv$8$ processor uses $10$ bits for an opcode for I$-$format instructions

and $5$ bits for a register.$)$

Decide the instruction formats. Give each of the formats a name.

Decide the number of fields each of the instruction formats will have.

Give each of the fields a name and decide the number of bits that will

be used to represent them. It is not necessary that you have the same

instruction formats as in the textbook. Even if you try to use one of

the instruction format from the textbook, you not necessarily have to

have the same number of fields as in the textbook.

Decide how each of the instructions is represented in machine code.

Aim to minimize the number of unused bits in the machine code. Please

ensure that for each instruction, examples are provided in both assembly

and machine code. $($See Section $2\mathrm{.}5$ of the textbook for machine code

representations of the instructions of LEGv$8$ processor.$)$

It should be noted that you not necessarily have to use the same

fields or same number of fields to represent machine codes as used in

the textbook for LEGv$8$ processor.

Understand how all of the above are done in the textbook for a $64-$bit CPU.

You may like to consider only the concepts presented in Chapter $2$ of the

textbook when working on the project. For a set of sample instructions,

you may like to refer to pages $64-65$ of the textbook.

Beyond the textbook, you are not required to study or explore any

additional materials to complete the design project. If you, however,

decide to get ideas from other sources, such resources should be clearly

listed as a list of references.

The $16-$bit CPU with only $16$ instructions is not going to be a very useful

one but that is okay; we want to learn how to design.

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Clarification:

The following two lines of code do not represent two different

instructions. They are two examples of an instruction.

ADD X$0,$ X$2,$ X$3$

ADD X$1,$ X$2,$ X$3$

Speaking in another way, the above code can be executed by the same

hardware. Therefore, they represent the same instruction.

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How to start the project?

You are advised to do the following at first before you think about

doing the design project. This way you will i$)$ be benefited the most

for your time, ii$)$ have a good finished product in the end, and iii$)$

enjoy the project or at least it will be less boring.

a$)$ Watch two videos from Chapter $2$;

b$)$ Read the relevant Sections from Chapter $2$;

c$)$ Try to understand everything from those sections from Chapter $2$;

d$)$ If you are not clear about something, repeat above steps and seek help

from the instructor;

e$)$ Read the assignment multiple times and try to understand every words.

Allocate some time over several days to master the materials from

Chapter $2$ and then work on the design project.

Your instructor welcomes questions from you. Every question is good.

If you would like to have an in$-$depth conversation with your instructor

on the design project, it is highly recommended that you study all the

background materials in advance as listed above.

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How long the report should be$?$

Everyone will come up with their unique way of presenting the design.

As a result, the number of pages will vary from design to design.

There is no minimum or maximum page count requirement.

$-------------------------------------$Pleasee design this project make$-------------------------------------$