easy way to drive 4 8x8 Matrix?

Hello!

I would love to build a simple matrix application with my arduino.. how would it be the easiest to build a 4 8x8 (32x8) matrix, not RGB? I got a couple of MAX7221 around.. I once tried to use two of those but it didn't sync very well.. basically I will make a little message board and maybe later a clock and e-Mail status..

What about power? Will an arduino be able to light up 4 matrix (20mm x 20mm)?

How would I code a sequence that scrolls right to left using these 4 MAX7221?

I am quite a beginner and I would love to learn more about programming etc.etc. :D

Thanks for your help!

-andreas

did you read this thread?

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1225239439

Because, those displays are VERY cheap. 3x2 8x8 matrices OR 4x1 8x8 matrices. I have the 3 times 4x1 8x8 board, available on ebay from sure electronics. Will cost you about 10 bucks and you can interface it DIRECTLY with arduino. No more need for max7221 or anything…

http://cgi.ebay.nl/0832-LED-Dot-Matrix-Yellow-Display-Information-Board_W0QQitemZ250463056048QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3a50c2f0b0&_trksid=p4634.c0.m14.l1262&_trkparms=|293%3A2|294%3A30

available in green, yellow and red…

What do you mean by not sync well?

For 4 x 8x8 displays you will need to tie all of the rows together and drive them all at once. You would need to run your driver chip through a transistor array to get enough current. Then use your other drivers to run the columns.

It's been done a thousand times before and there is plenty of material online if you look around.