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Altera_Forum's avatar
Altera_Forum
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16 years ago

Takes too long to get address

I'm writing a simple program that reads and writes to RAM. If I want to write, I provide the starting address and a valid signal and I write to memory starting at that address until valid is deasser...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

I previously mentioned, that you have also the option to register none of the RAM block input signals, because they are already registered in the RAM. This would be my preferred method to achieve a fast design reaction. 

  process(clk,reset)
  begin
    if(reset = '1') then
      next_addr <= (others => '0'); -- not actually required
      cont <= '0';
    elsif(clk'event and clk = '1') then
      cont <= valid OR readEn;
      next_addr <= address + '1';
    end if;
  end process;
  
  store: ram4bits port map(address => address,clock => clk,data => input,wren => valid,q=>hold);
  address <= next_addr WHEN cont = '1' ELSE
    rwaddressstart;