What is it about LEDs that makes everyone interested?! I have been throwing ideas in my head about what can we do with LEDs for gadgeteer. The first one was LED7R, which is pretty sweet I must say. You have to see it love to appreciate it more But 7 LEDs is not enough, we want hundreds! But what if someone wanted less, what if wanted more? The answer is, expandable, thanks to dasylink.
I have seen this LoL shield for arduino http://www.sparkfun.com/products/9796 that looked promising but then found this video
This will be no problem as we should plan in making it expandable. You need one, get one, you need more, get multiple. Adding on, the processor may not have enough pin speed to control 1000 LEDs for example plus this will waste the processor time on something basic. This is also solved by the daisylink. The processor will only have to send couple-byte-bitmap of the LED matrix and then the little micro than handles daisylink can also handle the LED scanning.
The LED spacing must be perfect between LEDs and then it has to be the same if you have multiple boards. You could have thousands of LEDs and all should be at the exact same spacing. This can be taken care of by giving the board a shape like puzzle so when you place the board in matrix, they can mount to each other somehow.
One last problem, power! If you have 1000 LEDs, do not expect them to be all powered from the mainboard. Instead this module should have an “optional” way to power from separate power or from the mainboard.
Ok…I am off to design this but wait, what microcontroller to use? using avr is good because of the arduino IDE but then we can get 50mhz ARM processor for less money! Faster processor means faster refresh rate.
Also, will this be done charlieplexing or matrix? Matrix is easier and gives higher refresh rate. Charlieplexing is less power but can be very confusing! http://en.wikipedia.org/wiki/Charlieplexing
As this is another OSH design, you guys are invited to join in.
We need some feedback on, do you want this finished (SMT LEDs) or kit like LoL shield (TH LEDs)?
How many LEDs should be on one module? Remember you can have as many as you like daisylink.
How much do you think such module is worth?
Having RGB or multicolor LEDs is great for sure but will increase the cost much. Is this a must have?