The Verilog system tasks $readmemb/h are prepared to fill only a part of 
the memory but not to read only a part of the file. This is different 
from C. So, I would suggest that you increase the size of the memory so 
that the complete file is read with one single call of $readmemh. 
Afterwards you may process the data in chunks of 1000 samples out of the 
memory.

Is there any method where we can read chunks of datas from a file using 
verilog....

No.

It's quite simple to read the complete file. Why don't you do this?

i have tried but in icarus simulator the its reading upto 1980 
words....after that it is giving error as below
Error: Invalid input character

That's surprising! Are you sure that there is no invalid character in 
the file. If you delete the first n items does the error number stay the 
same?

thanks a lot for ur reply......s u r right sir....i found one invalid 
charachter over there now it is reading properly...

Hi

I have converted an image into text file in hex format. I want to 
further process these pixel values in verilog code. how should i do 
it..? i tried using $readmemh ... but i am not able to read the text 
file.. please can any one send me the entire code to access the pixel 
value...

Thanking you in advance.

Naz Saheb wrote:
> i tried using $readmemh ...
Show a little bit more of your code. And also some lines of the 
hex-file.

> but i am not able to read the text file..
Why not? What problem do you encounter?

thanks for the reply sir

i am not able to get where exactly i have to use $readmemh in my 
attached code.

i tried for simple program below but it resulted in an error that no 
ports are declared, whats wrong?

1

module text_read_write;

2

  reg [7:0] mem [0:4];

3

  integer m,i;

4

5

  initial

6

    begin

7

      $readmemh("mem_in.txt", mem);      

8

      m=$fopen("mem_out.txt");

9

      for(i=0;i<5;i=i+1)

10

         begin

11

           $fdisplay(m,"%h",mem[i]);

12

         end

13

      $fclose(m);

14

end

15

endmodule

text file values :
1
2
4
A
B...

Naz Saheb wrote:
>>> I have converted an image into text file in hex format.
Naz Saheb wrote:
> text file values :
If the attached img.txt has anything to do with your problem: there is 
no hex value inside this file! Its plain ASCII integer.

Naz Saheb wrote:
> i am not able to get where exactly i have to use $readmemh in my
> attached code.
Maybe you must generate a testbench for that module imageedge and feed 
that imageedge with stimuli read out of the img.txt. Am I wrong? Or what 
is this code snippet for?

BTW: Why the heck did you pack a 4kB Verliog file with the file 
extension .txt into a ZIP?
I unpacked it and attached is as a .v Verilog file to your post. Next 
time think and do it yourself, please.

sorry for the mistake sir...

sir can you please suggest how and where to assign the  text file values 
of hex format as an input to an INOUT port in verilog ???

Is it in the main module or the test bench???


In the attached code file 'bus' is declared as an inout port which is a 
bidirectional bus. i want to give text file values as an input to the 
bus..

how can i proceed sir??

Can't we read 2-dimensional text file to verilog test bench? I want to 
make it read like that. please help me in this regard. Whether its 
possible or not? if possible the way? Here I'm attaching the text file.

yk_learner wrote:
> I am trying to perform skin detection from an image in verilog.
For real life on real hadware or just in a simulation with a picture 
file?

> Could you please share some light on this
Pls start a completely new thread for a completely new question.

> From the image that is ready
What is a "ready picture"? In what way is that picture "ready"?


Just as a hint: after writing your post you should have a look at it 
like you would know absolutely nothing about your specific problem. 
Because thats also the way we see your problem. If you do not 
understand your problem with the information you supplied, then we 
will have the very same problem.

JamesLuiz wrote:
> Readmemb's file name argument contains non-printable characters
Its filename is ghi.txt, that's all printable chars...

Or do you mean the content of the file ghi.txt isn't really text, but 
instead it contains binary data? (**)

In that case a 'b' is missing at r+

See there: 
https://stackoverflow.com/questions/25024751/read-binary-file-data-in-verilog-into-2d-array



(**) if it contains binary data, why is it named "txt"?