Strange FFT Output

I normally write as follows:

---- write data_out to file
process(clk)
file file_out : text open write_mode is "filename.txt";
variable line_in : line;
variable tmp : integer := 0;
begin
if(rising_edge(clk))then
  if valid_out = '1' then
     tmp := to_integer(signed(data_out));
     write(line_in, tmp);    
     writeline(file_out,line_in);
  end if;
end if;
end process;

Literally mate, you are a bloody hero. Don't let anyone tell you otherwise.

sorry, im having a problem using the ifft/fft, my state machines that control the megafunctions are working properly, as i get no errors from the fft error bus and i get sop and eop where i am supposed to get it, after and a the beginning of my fft/ifft length, the problem is that my data is all over the place. my N=1024, i ifft 3+3i(600 times) and padd with zeros, but when i fft the output of the ifft, some of the values give correct data, while some of the values are negative, help please, been working on this problem for a while now

Hi Sam_novice.

Thank you i solved the problem, my fft works, both in variable streaming and normal streaming, the problem was i was not watching the response of the sink_valid signal thank you

yes it does seem asserted all the time, but it is not, you need to put an option in your down stream fft state machine, that says that when sink_valid is high you sample and when it is not, you do not sample. This is made clearer in the Avalon interface specifications, read the section about data streaming and its control

I wrote to you on message board the following, did you make use of my suggestion: