Overhauling LED marquees

led-sign

In a previous job, [sprite_tm] was responsible for wrangling many different LED text ad marquees. The hardware was fairly simple and he always figured they could be pushed much further with a little work. He recently acquired ten 32×16 LED displays a decided to see what he could do with them. By the end of the project, he had full motion video running on the display. This is a great project to read up on if you’ve ever wondered about LED matrix displays. He starts by reverse engineering the electronics on the board. He then attached an ATmega88 to drive the display module. Multiple display modules were daisy chained together over serial. The article covers PWM control and refresh timing as well. Check out one of a few demo videos below.

Comments

  1. john says:

    Wow, simpsons on an LED display, that’s awesome.

  2. Adam Ziegler says:

    watch?v=ti_soK51y-Q has the Simpson display.

  3. Adam Ziegler says:

    Wow… just realized that HAD doesn’t actually upper->lower case the stored input. It is handled with a style of text-transform: lowercase;

  4. ssh! no one is supposed to know!

  5. Tony says:

    Very awesome. It’s amazing how you can still make out what pretty much everything is on such a low res display. Very cool.

  6. cde says:

    @ Adam, I figured that out during the whole CAPSLOCKS day thing. Even posted about it. All you need to override it is a user css and adding a
    * { text-transform: none !important;}

    line to it. Poof, no more forced lowercase or caps on any site.

    Also, Sprite’s the man.

  7. Wwhat says:

    It’s interesting as a hack and he (and we) learned some stuff and he showed prowess, but really, by the end he must have put more cash in the project than the cost of a 22″ LCD, that’s the kind of thing that would hold me back, basically it’s done already (LCD=dotmatrix too) and available at shops, and I don’t really see a need for it.

  8. cde says:

    @ Wwhat:

    Considering that part of the project started out as funded by his job and them paying him to do what he enjoys, as well as the “I built it my goddamn self” bragging rights. Add that he probably had the discretes and the AVR’s already, so just had to buy the (Used and discounted) led displays (5€ each, so 10 * €5 = 50€) it more then balances out. (Comes out to about 12 USD per LED Display + AVR). Worthwhile I would say.

  9. Dim says:

    actually he didn’t buy ten 32×16 led matrices but 8×8 and combined the 8 of them into a 32×16 display…Just thought to mention that :)

  10. Dim says:

    disregard that , i didnt read carefully the article :)

  11. henk says:

    I have 4 of these as well, I got them from the same source as sprite.

    They are old bus station displays, that’s why they’re so cheap.
    If you watch closely in the video’s you can see the burnt-in leds from the bus-numbers etc…

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

Join 92,354 other followers