8 bit Processor

[tech_vaibhav_eee]

Hello,
I am presently working on the design of a 8-bit microprocessor. I am working on my own and dont expect any help from the professors.So, basically my source of knowledge for this project would be internet. I want to keep the project as simple as possible with basic arithmetic and logical instructions and some load/store instructions.
I understand all the digital blocks needed for the design such as memory, register file, ALU, shifters etc. I also understand that the first step needed is to design a datapath and I am working sincerely towards it.
Now, coming to the problems I am facing , I am not being able to understand as to how an indivisual instruction will be executed.
for eg. , suppose I give mov Ax,[Bx] , I need to understand how the hardware executes this instruction.Specific doubts are:
1)Will the whole of the instruction be executed in 1 clock cycle or multiple clock cycles are needed.
2)Should I make the instruction 8 bit or 16bit. Basically , how do I decide the size or the instruction.
3)If the instruction will be 16 bit , only 1st 8 bits will be fetched in the first clock cycle and next 8 bits in the second clock cycle.So, in such a case , how does the hardware executes the instruction.

My opinion: I believe that since my instruction set is small , and since I will be using only one or two addressing modes , 8 bits are enough for a single instruction.
But , at the same time , I feel that the instruction can not be executed in a single clock cycle.
Basically, as you can infer from my my post , I am really confused as to how an indivisual instruction will be executed at the hardware level.
I have a lot more doubts as well but i am not able to express them here.

If someone can explain me the exact working or give me links to materials which can help me, I would be greatful.
Infact , If my approach to the designing of a microprocessor is not correct , I would love if someone could correct me or guide me through this project.
Please , do not ignore this post and help me in any possible capacity

 

[blueroomelectronics]

Based on your question, previous posts and apparent skill level I'd recommend picking something else as your project.

 

[tech_vaibhav_eee]

Thanx for the reply.
I know that I dont have much knowledge about processor design at present , but I feel that instead of moving to a different project , I should gather the knowledge which could help me move forward with this project.
And , as I mentioned , I dont expect you to answer the question but guide me towards the right direction. You can help me by providing links to materials which could help me in understanding the fundamentals.

 

[kamdy]

Before you proceed in this project i recommend that you read the architecture of a known processor such as 8085 or Z80 and understand how the instructions are fetched and executed by the control unit of the processor

 

[MikeMl]

Before you proceed in this project i recommend that you read the architecture of a known processor such as 8085 or Z80 and understand how the instructions are fetched and executed by the control unit of the processor

Or a PIC (MicroChip).

 

[OlPhart]

I'd go even simpler, research RISC: reduced instruction set. Freescale has a flavor of this as the 9RS08 series.

Another angle is what's called "bit slice". It's a processor constructed of individual chips that handle N bits each: 8 bit data uses 8/N slices (chips). The AMD 2901 was a 4 bit wide slice, circa 1975. These are from the era when processor chip speed was slow (<4MHz), so you went with wide data; 24, 36 even 48 bits.

It'll be easier to understand how a processor works internally from these, than from the CISC (complex instruction set) processors we typically use. Good Hunting... <<<)))