Computer Logic and Electronics
Hi. I have a few questions i dont know how they really works and it would be appreciated if some one answeres.
1. Describe the function and interation of a control unit, arithmetic unit and memroy registers in a simple central processing unit?
2. illustrate how buses move data and instructions between memory and CPU?
3. Describe the role of flip-flops in the flow of data. Explain how flip-flops can be built using the siple logic circuits? How are flip-flops used as information storage.
Thank You
Re: Computer Logic and Electronics
Why don't you try your text book?
Re: Computer Logic and Electronics
Re: Computer Logic and Electronics
Quote:
Originally Posted by gstercken
Now why didn't i know about this FAQ.. Would have loved to have used it quite a few times... :D :D :D
Now bookmarked for future reference.....
Re: Computer Logic and Electronics
Quote:
Originally Posted by gstercken
I'd rep you but we're in chit-chat :D
Re: Computer Logic and Electronics
:D :D
Couldn't believe we have an FAQ on that ;)
I'll bookmark it too :p
Re: Computer Logic and Electronics
Quote:
1. Describe the function and interation of a control unit, arithmetic unit and memroy registers in a simple central processing unit?
the main registers are :
- Data Register(DR) : at fetch-time it has op-code and in execution time it has the addressof operand
- Address Register(AR) : at fetch-time it keeps the address of op-code and in execution time it has the address of operand
- Instruction register(IR) : it has just the op-code
- Program Counter (PC) : the address of next instruction
- Accumulator(AC) : a place for saving the results or other necessary computations
the order of execution of an instuction (ADD instruction)
- CPU activaeted? yes :goto 2
- AR <-- PC
- DR <-- M(AR)
- IR <-- (op-code)DR , PC <-- PC+1 , DECODE instruction
- switch ADD Goto 6 , switch LOAD Goto ... , switch ... Goto ...
- AR <-- DR(Address)
- DR <-- M(AR)
- AC <-- AC+DR
1 -- 4 : fetch Cycle which is common for different instructions
5 -- 8 : execution Cycle
every proccessors have a number of function which Control Unit should execute them in the above order
for example
Code:
C3 ------- IR <-- (op-code)DR
C6 ------ PC <-- PC+1
in fourth clock cycle,control unit would open the gates related to C3 and C6
Quote:
2. illustrate how buses move data and instructions between memory and CPU?
there are buffers there,Memory Buffer Register(MBR) & Memory Address Register(MAR),you give decoders MAR as input addresses and get the content of memory in MBRs
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3. Describe the role of flip-flops in the flow of data. Explain how flip-flops can be built using the siple logic circuits? How are flip-flops used as information storage.
Latch are made form two NAND or NOR gates
http://www.play-hookey.com/digital/images/rs-110.gif http://www.play-hookey.com/digital/i...rs_nor-000.gif
by adding clock to latch you have flipflop,which are several kinds(SR,TR,JK,D-FF,...)
for avoiding Race problem you can use two FFs for synchronizing them with clock cycles (master-slave FFs)