actually I want to add program counter with following circuit
I want to see that how does program counter with this circuit
[suppose AND, OR gate are two input 4 bit Ic]
program counter
need help on Program counter
- Thread starter abhimanyu143
- Start date
I want to see that how does program counter with this circuit
[suppose AND, OR gate are two input 4 bit Ic]
program counter
yes but I don't understand how to connect program counter. as you said I need counter and mux to make program counter.
that's why I am asking you how to connect program counter ?
that's why I am asking you how to connect program counter ?
Program counter
Input signal
clock signal
clear signal
8 bit low address
8 bit High address
output signal
8 bit data signal
I think mux is use for following
low address means - output of multiplexer should (0)
high address means - output of multiplexer should (1)
when address mux is ( 0) then this is end of instruction and pc incremented for next address
when address mux is (1) then execute jmp or branch instruction
I don't understand how does 16 bit address load from 8 bit data bus ?
If there is any link or picture that define reason please attach link
Wow, it has been almost a week and I dont see much progress in your PC design. Only wild guesses on what the muxes are doing, and speculating how 8 bit data bus can be connected to 16 bit address bus .....
As for any links for this, sorry no, I dont have any. Your google is as good as mine. I have never taken such a tedious task to design a similar mcu core like the 8051. Even looking at the verilog codes on the open-source code for 8051 gave me lots of headache, not to mention that I just started to learn VHDL on Altera platform. Actually you are more ahead of me as your are using Quartus II while I am still using MAX+II plus.
OK. enough blah-blah-blah. Have you taken my advice and look at the Architecture block of the 8051 on its datasheet? Here's one that I have simplify with MSPaint.... I removed all the unnecessary stuffs and left only the essential blocks for you to implement. I even removed the B register which I think you dont need it. If you can, you can even get rid of the crystal clock and replace with 2 LM555 - one for astable clock pulses and the other for monostable just to step the instructions.
I'll be taking a short vacation trip with family next week. After returning, I'll have a 3-week on the job-travelling to a remote town doing installation works. Dont be surprised if I just disappear from the forum for a while.
Allen
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One thing I must say..... To prepare materials for answering to all the questions asked by a poster is not easy. We take time to prepare the stuffs and sometimes have to flip through pages from my book-shelves and refer to past notes that I have taken from time to time.
So I hope the questioners would value the answers that we have given. BTW did you read through all the posts that you have asked about your 8051 core design? I am sure you've left out valued informations on all those posts. My master once told me that "If you cannot recognize the value of a diamond, you'll walk pass by one even if it is lying on the roadside in front of you; thinking that it is probably glass."
And dont say "Let's forget what we have discussed and just tell me this, this and this". I think that is rude and hurts people who tried to help you.
Allen
So I hope the questioners would value the answers that we have given. BTW did you read through all the posts that you have asked about your 8051 core design? I am sure you've left out valued informations on all those posts. My master once told me that "If you cannot recognize the value of a diamond, you'll walk pass by one even if it is lying on the roadside in front of you; thinking that it is probably glass."
And dont say "Let's forget what we have discussed and just tell me this, this and this". I think that is rude and hurts people who tried to help you.
Allen
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I am really sorry Allen , I don't want to hurt someone. I said, because I want to understand simple PC and then I want to go for complex PC. I will remember. I will never say these word again
Ok , I Wish you a very happy journey
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I read the datasheet and I looked diagram. Its very tough for me I don't understand because there are timing and control unit , DPTR stack pointer involved in diagram
my knowledge : I understand registers , program memory , data memory , ALU, instruction Decoder and strugling with PC
I just want to ask you , can we start with counter and multiplexer? once I understand basic of PC , then I will go for 8051 PC
we have 16 bit program counter. we can load any bits. we can load Top four bits , middle four bits , bottom four bits , bottom 8 bits using multiplexers
just example for PC
for short jump (only load top four bit of PC )
for long jump (only load center four bit of PC)
for subroutine (load bottom four bit of PC)
My problem , I made red connection , I don't understand that connection
Did you read your other thread here?
http://forum.allaboutcircuits.com/threads/alu-with-pc-need-help.105475/
Allen
http://forum.allaboutcircuits.com/threads/alu-with-pc-need-help.105475/
Allen
i have read it just now. thank you very much ,you help me lots , I don't have word for you ,
Now I need advice how to learn step by step . what is my next step. what should I do Next. I have to make basic PC or I have to make PC for 8051
The PC design is considered almost complete. We would see if it is needed to add the DPTR (Data Pointer), PC incrementer and buffer later. The next step is the RAR, PAR and RAM to be added to your design.
For RAM you can use either 2114 (1Kx4 bits) or 6116 (2Kx8 bits). Do your connection with reference to the block diagram. Should be an easy task.
Allen
For RAM you can use either 2114 (1Kx4 bits) or 6116 (2Kx8 bits). Do your connection with reference to the block diagram. Should be an easy task.
Allen
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I have done the schematics with Program Address Register, Ram Address Register and RAM (6116) added. But I want to see how you've done it before I post mine.
You can try to solve the problem on how to connect the PSW to the ALU as well. As the ALU only have the Cout flag, you have to find a way to implement the "zero flag" i.e. when the result of adding or subtracting 2 numbers = 0. That should be a piece of cake to you. Another thing is that your "Immediate Regiaster" is sitting in between the Data Bus and Accumulator; this would block any data sent from the ALU to the ACC. You have to do something about it too.
Allen
You can try to solve the problem on how to connect the PSW to the ALU as well. As the ALU only have the Cout flag, you have to find a way to implement the "zero flag" i.e. when the result of adding or subtracting 2 numbers = 0. That should be a piece of cake to you. Another thing is that your "Immediate Regiaster" is sitting in between the Data Bus and Accumulator; this would block any data sent from the ALU to the ACC. You have to do something about it too.
Allen
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I have got a lot of good design ideas from the link pointed by Ian Rogers of ETO here
http://www.bigmessowires.com/2013/08/27/custom-4-bit-cpu-schematic-and-control/
The Architecture is here
And the complete schematics is here
From this I am going to split your 8-bit ROM data into two halves. 4 bits for instructions and the other 4 bits for Imm data for MOV a,#imm and MOV R1,#imm; OR upper 4 bits of the 12 bit address on the JMP instruction.....
So much for now until I return from my vacation.
Allen
http://www.bigmessowires.com/2013/08/27/custom-4-bit-cpu-schematic-and-control/
The Architecture is here
And the complete schematics is here
From this I am going to split your 8-bit ROM data into two halves. 4 bits for instructions and the other 4 bits for Imm data for MOV a,#imm and MOV R1,#imm; OR upper 4 bits of the 12 bit address on the JMP instruction.....
So much for now until I return from my vacation.
Allen
ok I am trying to make that design on proteus software. I have few question.I am also searching . I can't place all component in one sheet. I have to add another sheet. how to connect component from different sheet. how to see different sheet in one paper.
Read post #39 of your own thread here
http://forum.allaboutcircuits.com/threads/rom-memory.105066/page-2
I have anticipated that you'd get this problem before you ask.
Allen
http://forum.allaboutcircuits.com/threads/rom-memory.105066/page-2
I have anticipated that you'd get this problem before you ask.
Allen
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Hello Allen ,
I need few time. I am reading some link and material
I have modified my own circuit
it can execute some instruction LOAD , store , MOV, ADD, SUB, AND ,OR
