8 bit processor ?

8 bit processor

main component for processor

ALU 8 bit

Q1 I have option for decoder
 decoder 2 to 4
decoder 3 to 8

which decoder circuit  I need for 8 bit processor

Q2 I have option for multiplexer
multiplexer 2 to 1
multiplexer 4 to 1
multiplexer 8 to 1

which multiplexer  circuit  I need for 8 bit processor


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vead (author) 2 years ago
ALU perform following function

AND logic

OR logic

NAND logic

NOR logic

X or logic

X nor logic



I am not going to design for specific purpose

don't mind I made some simple specification for 4 bit processor

specification for 4 bit processor

1)4 bit ALU

2)3:8 decoder

3) 4 bit A register ( data register )

4) 4 bit B register (data register )
5) 4 bit Instruction register
6)4 bit address register
iceng2 years ago

So .... for your knowledge here is a simple 4 to 7 DECODER and driver that only needs four uP pins to drive 7 display lines to present any digit.

It would be a 3 to 7 Decoder if you only needed to display the digits 0 through 7

This IC accepts four binary digits (A,B,C,D) and drives the ubiquitous 7-segment LED or LCD numeric digit.

The 7-seg can display 0,1,2,3,4,5,6,7,8,9,a,b,C,d,E,F all of the 16 digits of 2 /\ 4

iceng iceng2 years ago

Here is what you ca do with an 8 bit uP

7Segment.MOV(272x480) 16 KB
vead (author) 2 years ago

I want to know basic information I am not really going to make I just ask for Information

processor is 8 bit and ALU is 8 bit

then I need decoder

but I don't understand which decoder will be used

I have read types of decoder

decoder 2 to 4
decoder 3 to 8.....etc

rickharris vead2 years ago

Sorry but I still don't understand what your problem is BUT it sounds like homework. If it is then read up the links below.


is a better link to the circuit I linked to for the Acorn Atom - a full 8 bit computer will all the bits you need.







rickharris2 years ago

The very nature of your questions suggests that you do not have enough knowledge or skill at this stage to do what your trying to do.

There is no point in building an 8 bit processor, you may as well buy a 6502 or Z8


is the full cct diagram for a 6502 computer (the acorn Atom) including the video interface.

I don't understand the question. WHAT are you trying to do ?