Need Help, Need Help LCD in Spartan 3AN using VHDL

M Iqbal Guest 2011-05-31 05:14 #2205486

Rate this post

•	▲ useful ▼ not useful

I need help regarding using LCD on Spartan 3AN. I made a LCD Driver 
following the manual, but it still didn't work. I would feel grateful if 
somebody can point out the wrong in my code.

Here's the code for the entity

http://pastebin.com/dtM9P5k1

Here's the LCD Driver

http://pastebin.com/YhHtYyBe

Here's the UCF File

http://pastebin.com/Gr2Vq9wh

Thanks beforehand.

Reply Quote Edit Move Thread sperren Anmeldepflicht aktivieren Anpinnen Delete topic Thread mit anderem zusammenführen Report post

Duke Scarring Guest 2011-05-31 08:22 #2205544

Rate this post

•	▲ useful ▼ not useful

Did you simulate your code with e.g. modelsim? Did you have a testbench?

Duke

Reply Quote Edit Delete Report post

Lothar M. (lkmiller) Moderator (Company: Titel) 2011-05-31 08:59 #2205576

Rate this post

•	▲ useful ▼ not useful

Theres a neat part of code for a testbench
Beitrag "Re: Initialisierung LCD-Display"
Its German, but maybe Babelfish is able to translate it... ;-)

BTW:
> http://pastebin.com/dtM9P5k1
You can attach your code directly here in your post...

Reply Quote Edit Delete Report post

M Iqbal Guest 2011-05-31 11:15 #2205749

Rate this post

•	▲ useful ▼ not useful

Thank you all for your responses. I have updated my LCD Driver Code, now 
it can initialized (there's a blinking cursor on the display). But I 
can't seem to write any data into it.

process(Clock) begin
    if rising_edge(Clock) then
      case State is
        when Init =>
          State <= Print;
        when Print =>
          if Busy /= '1' then
            State <= Printb;
            Data <= "00110000";
            Write_Now <= '1';
          end if;
        when Printb =>
          Write_Now <= '0';
          State <= Idle;
        when Idle =>
          State <= Finish;
        when Finish =>
      end case;
    end if;
  end process;


I just want to write a simple '0', but the display didn't change. Thanks 
again.

Attached files:

LCD_Driver.vhd (11.5 KB) | highlighted code
LCD.vhd (5.23 KB) | highlighted code

Reply Quote Edit Delete Report post

Lothar M. (lkmiller) Moderator (Company: Titel) 2011-05-31 13:27 #2205944

Rate this post

•	▲ useful ▼ not useful

To keep things short:
You MUST verify your code with a testbench. And at least have a close 
look at the waveforms on the simulator, and check out wether the timing 
fits the LCD or not...

And in your case this is the most easy thing to do:
just generate a clock and apply it to the LCD module.

Reply Quote Edit Delete Report post