Need help picking arduino

Hello forum, ive been looking to get the arduino for quite some time now, but have been looking at other projects to try to gain some footing before diving in myself.

What I have noticed is that most people use the power house Duemilanove or similar chip-set, but honestly its a little to big for what I want to use the arduino for this time, I will probably get a UNO some time in the future, but for now i need something compact that have the power to do what i need

So what i need my arduino to do is: Read the serial data from a Cue:Cat PS/2, Uploading the data to a sql server using a Libelium GPRS Shield, displaying data on a small serial lcd, receive input from a 1-9 keyboard, And possibly using a SDD to store temporary data.

I want to use this as a learning project adding more and more features to it as i go. Starting with the CueCat, and displaying the string on the lcd.

Any suggestions on what arduino to use, or any advice would be greatly appreciated!

-Thomas Hodnemyr

Don't look now but the Duemilanove is just an older version of the Uno. They are functionally (almost) identical, sharing the same microcontoller chip, the same connections and the same physical size. Either will do what you want although you'll probably need to use software serial for the LCD.

that have the power to do what i need

Power is an ambiguous term. All modern Arduinos have the same computational "power." If you want smaller, get a Mini or Pro-Mini. You'll have to add a USB-to-serial converter and/or header pins, but they are small.

Or you could just get the credit card sized Uno/Duemilanove and some variant of a Proto-Shield. That would easily match the "power" needs of your project.

Is there enough I/O on an arduino to do all that?

PS/2 will need data & clock (and power & gnd) the GPRS shield uses a bunch more, serial LCD will need several more, if not some specific pins for I2S or SPI, 3x4 keypad will need 7 if done normally using the keypad library, and SDD is another shield itself?

PS/2, LCD, keypad are all pretty doable, have to see which pins the shields require as dedicated and if there's enough left for the others, or if you have to start adding aux hardware, shift registers, etc. to accomodate the non-shield(s) parts.