 |
By: ceka (offline) on Sunday, July 12 2009 @ 04:12 PM PDT (Read 3150 times)
|
|
|
ceka |
| ceka |
|
Could Peggy architecture drive, say 2000 or 3000 leds?
How would one go about expanding?
Could Peggy architecture drive 2000 or 30000 rgb leds?
How would one go about expanding the architecture?
Does the Arduino have enough horsepower, or would a more powerful processor be required?
|

Apprentice
Status: offline
Registered: 02/16/09 Posts: 5
|
|
|
|
|
 |
By: Windell (offline) on Sunday, July 12 2009 @ 04:39 PM PDT
|
|
|
Windell |
| Windell |
|
>Could Peggy architecture drive, say 2000 or 3000 leds?
>How would one go about expanding?
Maybe, depends how you laid it out. There are always tradeoffs: more LEDs can easily be added at the cost of refresh rate and/or brightness. You'll also need to worry about the power supply, and the properties of the row-drive transistors as you go to larger sizes. The Peggy architecture can easily-- without significant changes be enlarged to 25 x 32 (800 LEDs), and if you wanted to add a few more transistor drivers you could easily get to 30x32 (960 LEDs). By changing how the demultiplexers are wired (and adding two more transistors yet) you could get to 32x32 (1024 LEDs)
>Could Peggy architecture drive 2000 or 30000 rgb leds?
>How would one go about expanding the architecture?
Just rephrase that as "Could Peggy architecture drive, say 6000 or 90000 leds?" RGB LEDs are no different to drive than three independent LEDs. But, figure that you need 6+ Peggy's worth of hardware to drive 6000, or 88+ Peggy's worth of hardware to drive 90,000 LEDs.
>Does the Arduino have enough horsepower, or would a more powerful processor be required?
"Arduino" is not a type of processor. The "smart" way to do this-- no matter what processors are involved -- is to have a master controller that controls lots of boards each with a modest number of LEDs. Peggy boards can be used this way-- sent commands from a master controller.
Windell H. Oskay
drwho(at)evilmadscientist.com
http://www.evilmadscientist.com/
|

Evil Scientist
 Status: offline
Registered: 06/15/06 Posts: 1932
Sunnyvale, CA
|
|
|
|
|
 |
By: ceka (offline) on Tuesday, July 14 2009 @ 10:15 PM PDT
|
|
|
ceka |
| ceka |
|
"Arduino" is not a type of processor. The "smart" way to do this-- no matter what processors are involved -- is to have a master controller that controls lots of boards each with a modest number of LEDs. Peggy boards can be used this way-- sent commands from a master controller.
I realize that Arduino is not a processor, but might it be a candidate (AVR) as a master controller? If not, what would be? It appears to have a programming language and I/O, what else would be needed for such a project, i.e. what could serve as a master controller? Also, if I were to use rgb's, wouldn't I need 4 circuit paths for each led? The Peggy board does not provide that. I'm also thinking a really bid display, say 8 feet tall and 20 feet wide, sort of a programmable billboard, although not for advertising. More for decorative or artistic displays. This is something that has been stuck in my head for some time. Finally, isn't power just a multiplier of the number of led's? More led's, more power (mv or ma)?
|

Apprentice
Status: offline
Registered: 02/16/09 Posts: 5
|
|
|
|
|
 |
By: Windell (offline) on Tuesday, July 14 2009 @ 11:32 PM PDT
|
|
|
Windell |
| Windell |
|
>I realize that Arduino is not a processor, but might it be a candidate (AVR) as a master controller?
Yes, it's a fine choice.
> Also, if I were to use rgb's, wouldn't I need 4 circuit paths for each led?
An "RGB" LED is nothing but three regular LEDs packaged together. Per actual LED element, you need two connections, not four.
>The Peggy board does not provide that.
Are you now talking about the existing Peggy boards, or are you still asking about a hypothetical setup based on the Peggy architecture?
If you're talking about something based on the Peggy architecture, yes it certainly can support RGB LEDs. (Meggy Jr RGB is one example, based on the same architecture.) However, you should know that the designs that we currently have out there are designed for 625 monochrome LEDs-- they won't fit 30,000, in RGB or monochrome.
> Finally, isn't power just a multiplier of the number of led's? More led's, more power (mv or ma)?
Only if everything else is constant.
Windell H. Oskay
drwho(at)evilmadscientist.com
http://www.evilmadscientist.com/
|

Evil Scientist
 Status: offline
Registered: 06/15/06 Posts: 1932
Sunnyvale, CA
|
|
|
|
|