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Altera_Forum's avatar
Altera_Forum
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17 years ago

Counter Problems

Hi, im trying to implement a counter which counts positive, negative, or both edges of an incoming signal. It works, but if I give 10000pulses to it it counts only between 9980...9997. The interna...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

Your code is too nested and complicated...

the following idea of counting may help 


 
signal count : signed(32 downto 0);
signal temp : signed(1 downto 0);
 
process(reset,clk)
begin
if reset = '1' then
    in_signal_d <= '0';
    temp <= "00";
    count <= (others => '0');
elsif rising_edge(clk) then
 
   in_signal_d <= in_signal;  -- your incoming signal
 
   if count_up = '1' then
        temp <= "01";        --   +1
   else
       temp <= "11";         --   -1
   end if;
 
   if in_signal /= in_signal_d then   -- either edge
      count <= count + temp;
   end if;
 
end if;
end process;
 
cnt <= std_logic_vector(count);