Hello
I am trying to connect 27256 eprom with 74ls163 counter. As my understanding 27256 has A0-A14 address and D0-D7 data bus. Actually I want to see how PC work with ROM memory. I am trying to explain if somewhere wrong. Please correct me.
ROM is permanent memory, once it programmed. It doesn't change its data.
Here is small example where data and instructions stored in program memory.

Address           data
Address 1        01110000
Address 2        01101110
Address 3        10010001

Now program counter read first 0111000 and store into instruction register. Than read second second and stored into instruction register same for third, read 10010001 and stored into instructions register. No instructions
Please look at diagram. If all is correct than I will try to add instructions register.

 

You absolutely cannot have RCO connected to your Enable signal. That would be two outputs driving each other. We had some colorful phrases for two TTL outputs fighting each other.

 

The circuit doesn't make much sense to me. Why would you load data from the EPROM into a counter? Using latches would make more sense.

How are you incrementing the addresses of the EPROM? How are the EPROM control pins being driven? Any chance of tri-stated EPROM outputs being loaded into the counters (which should be latches)?

 

That is some questions whose answer I am searching. I have both ROM and program counter in circuit. Can we start with this circuit just for learning

The program counter steps you through a program. Does the EPROM contain a program you want to execute?

 

Does the EPROM contain a program you want to execute?

Yes eprom store data, instruction. I have explained in my first post with example.
Can you help me to understand how does program counter increment or load address . If possible can you explain with example

 

I have explained in my first post with example.

Your first post wasn't very clear.

Can you help me to understand how does program counter increment or load address .

Technically, the program counter is just a register that holds the address of the instruction currently being executed. In some computers, it's called CIR (Current Instruction Register). Computers that use CIR will most likely also have an NIR (Next Instruction Register).

 

Your first post wasn't very clear.
Technically, the program counter is just a register that holds the address

Yes I know the definitions of ROM, counter, register. But I need help to understand basic. How they work together. Can we start with very small example
Program memory
Address 8 bit wide
Data 4 bit wide
Read enable pin
Program that being to execute
MOV R1#0010
MOV R2#0110
ADD R1,R2

Program counter
Data 4 bit wide
Load pin
Enable pin
MOV R1-XXXX, PC read data at address 1
0010- PC read data at address 1
MOV R2- PC read data at address 2
0110- PC read data at address 2
ADD R1,R2- PC read data at address 3
Does this make any sense?

Small memory with small program counter

 

Yes I know the definitions of ROM, counter, register. But I need help to understand basic. How they work together. Can we start with very small example

This article seems to have decent information - https://en.wikipedia.org/wiki/Central_processing_unit