Re: diagram (4 sparkfun button pads max7221)

Forum 2005-2010 (read only) Hardware Interfacing
1

im telling you right now, you WILL be sorry if you don't use rgb led's....

they are pricey, yes. They are more confusing, yes. And they will annoy you, yes. BUT they will be worth it!
once you have your single light monome ( or however you spell it ) working, ull be like "this is pretty cool, but this color sucks balls!" and you will also want multi color features, to make it look beautiful! And even if you really don't want to use all 3 colors, you can hook up 1 color for now, and you will still have 2 colors left to use anytime you want them!

sorry that i didn't answer the primary question, but i just had to speak my mind...

buy them from superbrightleds.com or whatever that site is called, they are only 1.50 each.... and make sure it's common cathode!

2

they are pricey, yes.

buy them from superbrightleds.com or whatever that site is called, they are only 1.50 each.... and make sure it's common cathode!

I got 100 for $30 (inc shipping) off eBay. :slight_smile:

Sorry I'm not familiar with those button pads either. :frowning:

3

i hooked the led columns and rows tonight to the 7221 as in the diagram and everything works great, had one cut trace but that was easily fixed.

now to get the shift registers going.

4

UPDATE: deleted first post because i couldnt modify it. here is the new working circuit.

im building a monome compatible device, using 4 of the sparkfun 4x4 button pads, im only using 1 of the anodes though as im using single color led's. i had a hard time getting the 7221 to work until i added decoupling capacitors so maybe i should have some more stuff thrown in? im also just assuming that i can joint the 4 4x4 segments together at the endpoints like in the diagram.

http://www.flickr.com/photos/unsped/2254118152/

finally got it wired up and working, need to work on the software tomorrow though.

5

thanks alot, now my first post makes me look like a weirdo! lol

those rgb led's that you got from ebay, where they diffused?

im also sick, cuz u paid 30 bucks for 100, and i paid about 30 bucks for 16.....That hurts my soul

6

those rgb led's that you got from ebay, where they diffused?

Nah but I just painted them with white paint. Looks brilliant.

7

lol sorry big93 i wish it would have let me edit it.

im calling it a night, but i have all the hardware finished i think. i have some rudimentary software that detects the button press shift value and sets each led row to that value.

now i have to multiplex the shift-out outputs to (currently i just have them all set high) and work out the conversion factor to get that to line up with the max7219 addressing (as the rows and columns for the registers vs. the max are rotated 90 degrees.)

ill need to have some 8x8 bit arrays, one for buttons one for led's

then to implement the monome protocol. at least no more wiring (it is quite a mess lol) until i get ready to put them on a proto pcb and off the breadboard. since its running the monome protocol which is a single color im saving rgb functionality for other but similar projects.