First complete project, how should I start?

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I am designing my first proper project after playing for a few weeks. I am looking to create a 7x6 RGB led matrix, but I am confused by how to go about interfacing with them. I've thought about a 795, or perhaps a max7219 (well, two of them as i will be utilizing only RG from the leds).

Cost is obviously a factor so I have thought about using simple red and green leds, but the wiring (though not much more than rgb) is hurting my brain :wink:

Is there an alternative to the two ICs above? Am I biting off more than I can chew? The programming shouldn't be an issue, I've been coding for 10 or so years, however this is my first foray into electronics.

I also noticed that the maxim chips depend on a common cathode, i fear that they are significantly more expensive (rgb at least), is there an alternative for common anode that takes as few pins as the maxim?

(btw, I will be using a duemillenove)

Thanks in advance for any help you can provide!

ps, any ideas when 019 will be out? My previous project is on hold due to the #146 issue....

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I also noticed that the maxim chips depend on a common cathode, i fear that they are significantly more expensive (rgb at least)

No I got them from ebay at the same price.

You need separate LEDs as you can't common anodes (or cathodes) on separate chips because their multiplexing oscillators are not synchronised.

Also do you want on / off control or brightness control of each LED.

Am I biting off more than I can chew?

I think so.

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Just simple on/off control.. If I can get rgb's that will work with the maxim for around $1 per, I really do think I can do it, I am just trying to find the cheapest solution...

I am willing to do the wiring for separate red and greed leds (so cheap, so very very cheap), so I was thinking of just using two 7219's one each for red and green, since it will only be two arrays of 42, it shouldn't be nearly as hard as some of these 3000+ matrices i've been reading about...

Essentially, I was just hoping to find a cheap way of using rgb's to keep the wiring a little cleaner, not to mention the visual look being much better with single evenly spaced led's as opposed to two offset evenly spaced leds...