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Design Languages >> Verilog-AMS >> try to read a file
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Message started by sunnysunnyho on Aug 2^nd, 2011, 7:48am

Title: try to read a file
Post by sunnysunnyho on Aug 2^nd, 2011, 7:48am

Hi.
I am trying to read a file from my verilog-AMS program (.csv, it is a lookup table with 2 lists of arrays).

real code[41:0];
real thresh[41:0];

initial begin
openfile = $fopen("file", "rb");
readfile = $fscanf("file", "%g %g\n",code[40:0],thresh[40:0]);
end

ncvlog: *E,NOPSOM file,33|72): Part-select or indexed part-select cannot be applied to memory [4.2.2(IEEE)].
readfile = $fscanf("file", "%g %g\n",code[40:0],thresh[40:0]);
|
ncvlog: *E,NOPSOM (file,33|85): Part-select or indexed part-select cannot be applied to memory [4.2.2(IEEE)].
module testlib.adcdiscrete:verilogams

The $fopen part of the codes is OK. The syntax/s of the $fscanf function is the same as the one in the manual.

I have no idea what's going on :( :-[

Title: Re: try to read a file
Post by Ken Kundert on Aug 2^nd, 2011, 9:17am

My guess is that you cannot use a range of indices on a real vector. Perhaps if you rewrite the code by adding a for loop so that you only access one value in the array at a time.

-Ken

Title: Re: try to read a file
Post by sunnysunnyho on Aug 3^rd, 2011, 2:23am

It is still not working :(
To try to solve the problem/s I created a program which just open, write and read a .txt file.

module readfile ( );

integer file;
integer readfile;
integer code;
integer a;

initial begin

a=999;

file = $fopen("/home/sunny/Desktop/loadfile/testing.txt", "rw");
$strobe("\nfile OK? = %d\n", file);

$fwrite(file, "%g", a);

readfile = $fscanf(file, "%d\n", code);
$strobe("readfile OK?=%d", readfile);
$strobe("code = %d\n", code);

end

I can open and write to the file (it shows '999' in the .txt), but I cannot read from the file, in fact, the variable readfile returned as "-1" and the code returned as "x".

:( :-[

Title: Re: try to read a file
Post by Geoffrey_Coram on Aug 3^rd, 2011, 5:00am

I would expect you to need to close and re-open the file in order to read it. Or, at least, you'd need to "rewind" it (is there an $frewind?), because after writing, the file handle will point to the end of the file, and that's why you're getting an EOF error when you try to read.

Title: Re: try to read a file
Post by sunnysunnyho on Aug 4^th, 2011, 2:38am

Thank you very much for your help, guys!!