LED Clock

Posted by on May 5, 2007 in avr, led | 11 Comments

So this is my approach of an LED clock. There are zillions of LED clocks out there. Mine is some kind of retro and minimalistic version. It consists of

  • AVR ATmega8, 8 Kb, 4.096 MHz
  • Everlight 2.3″, LED Matrix, 8×5 LEDs
  • some resistors, capacitors and a quarz
  • optional serial connection for configuration

The LED matrix is used in landscape mode, that means it uses a very tiny font. Most characters fit in 3×5 pixels. The font supports only uppercase characters. Because the display has only 8 columns the message has to scrolled.

The display has the following features at the moment:

  • Displays a greeting message
  • Displays the current time, hh:mm:ss
  • Displays a custom message
  • Messages and current time can be modified via serial port

IMGP1238

Schematics
Here is the schematic of the LED clock. The Everlight 5*8 Dot Matrix was not available as part of the Eagle libraries, so I build the part on my own. It looks a bit clumsy as it is my first try to design components.

schematics

Here is a video of the LED Clock. You can see how it changes through different modes from telling the time to displaying a greetings message.

Click To Play
Click To Play

11 Comments

  1. Alex
    29. June 2007

    Nice!

    I’m mucking around with an LED matrix at the moment myself. I’m a bit stuck on the scrolling though, I can make it scroll one character at a time but it starts at the left hand side, so looks crap. Any possibility of seeing your code? In return, I’ve got an eagle part library for an 8×8 matrix that I’m sure you could alter to a 8×5 easily…

  2. Alex
    29. June 2007

    Hi Alex,

    just add more spaces to your string, that should help with the scrolling. The source is unfinished and as always without any warranty.
    Anyway, here you go …

    matrix.zip

  3. jfk
    25. March 2008

    hey,

    may you give me your eagle file for the dot matrix thing? i have a 7×5 one here but no files it anywhere. altering yours would save me a lot of time. =)

    greets

  4. jfk
    25. March 2008

    mh, just now i found a similar useful one: http://www.sensi.org/~svo/eagle/

  5. jfk
    25. March 2008

    let me correct myself: not as useful as yours would be.. :)

  6. Alex
    29. March 2008

    Hi jfk,

    the part has not been used in a PCB until now so I will not release something untested. It was my first part and it was a bit crappy. I think I will remake it.

    Cheers,
    Alex

  7. Andhika
    26. July 2008

    I’m sorry, I still don’t understand how to change the clock and messege via serial port. can you give the program or how to change them? And if i add more led matrix, which code should I change?I’m so intersting with this project. My plan is make this project for gift to my girl. can you help me? thanks before.

  8. Vlatko
    6. April 2010

    BTW, what happened to this project Alex? Never finished?

  9. Alex
    6. April 2010

    I often get stuck in prototyping ;)

  10. Mustafa Eksi
    10. June 2012

    Hi Alex

    Your device is really amazing, im very suprised.
    Is it possible to send me the bit fuse and the hex file of the device ?
    It were very nice of you..

    Thx
    best regards

  11. Alex
    11. June 2012

    Hi Maustafa,
    I don’t have any of the files any more, but as I remember, there were nothing special about the fuses.
    Cheers,
    Alex