error when reading datas from a file

[Altera_Forum]

Hi everybody, 

 I'm actually trying to make a pixel generator from a text file and i have an error in modelsim : (vsim-3543) TEXTIO procedure READ(INTEGER) : Parameter L designates an empty string.  my file seems like that :  3 1024 760 41 107 214 235 44 169 3 33 187 239 58 61 57 42 142 77 89 114 221 104 41 107 214 235 44 169 3 33 187 239 58 61 57 42 142 77 89 114 221 104  and my code is here:   FILE myfile : TEXT OPEN READ_MODE IS "fluxvid.txt";  BEGIN   PROCESS   VARIABLE fNumber : INTEGER range 1 to 3;  VARIABLE pnumber : INTEGER range 0 to 1024;  VARIABLE lnumber : INTEGER range 0 to 768;  variable buf : integer range 0 to 255;  variable buf_temp : unsigned(11 downto 0);  VARIABLE l: LINE;    BEGIN   READLINE(myfile,l); -- ... read a line ...  READ(l, fNumber); -- ... read the 1st element ...  READ(l, ipxl); -- ... and then the 2nd element  READ(l, jpxl); -- ... and then the 3nd element   IF (start_gen = '1') THEN  -- frame loop  FOR k IN 1 TO fNumber LOOP   fVal <= '1';  data_com <= (others => '0');   WAIT FOR 100 ns;  -- line loop  FOR i IN 1 TO lnumber LOOP   lVal <= '1';   -- pixel loop  FOR j IN 1 TO pnumber LOOP   READ(l, buf);   buf_temp := TO_UNSIGNED(buf, 12);  data_com <= STD_LOGIC_VECTOR(buf_temp);   WAIT FOR 10 ns;   END LOOP;   lVal <= '0';   END LOOP;   fVal <= '0';  WAIT FOR 100 ns;   END LOOP;   END IF;   END PROCESS;  Moreover, the data in the variable fNumber 41 instead of 3. I don't know where is my fault, i search on the web and didn't find the mistake.   Thx you for your answers !

[Altera_Forum]

Cant really see the issue, clearly its reading in the 2nd line. Are you sure the file is correct? I also notice there's no wait at the end of the process, this means the process will start again when it gets to the end.

[Altera_Forum]

NO Tricky, Martou78 is only reading the very first line, I can only find one single READLINE statement. 

So the READ in the pixel loop will fail. I'm almost sure that vsim will have pointed to that line ...

[Altera_Forum]

No it will read all the lines, as the process isn't permanently stopped with a single "wait;" statement. 

There are two problems I see in that code:[list][*]if start_gen isn't initialized at '1' (and by default it will be 'U') then the process will just read all the lines from the file and do nothing with them before going even one ps into the simulation[*]you never assign any value to lnumber and pnumber. By default they will be 0 so you never read the pixel values[/list]

[Altera_Forum]

Correct, I overlooked that missing wait statement. I fixated on the missing ReadLine in the pixel loop. But as I said, ModelSim will (mostly) give a clue on the line with the offending statement, which would have been the first Read() after the ReadLine().

[Altera_Forum]

Hi, thx for your answers, i corrected it and it works !