New guy with new project...

Hi guys, newbie to the whole microcontroller would but I'm a web-developer by trade. I currently have a Arduino Uno. I'm fascinated by the possibility of linking social media/web to electrical devices. Basically what I'd like to do is... when I get a tweet, I'd like to ring a bell and on two separate lcds I'd like to display different data... one will be a running tally of rings and the other being the user's name. I'm fully able to work with getting the data to the Arduino software but I need to know if A. this is possible and B. if you guys could help me get the stuff I need.

Basically one arduino needs to trigger an electrical motor (obviously doable), display data on one LCD and different data on another LCD. I have the Arduino and Ethernet shield, but what should I get in terms of bread board, jumpers, pins etc. Also I was looking at these LCDs https://www.sparkfun.com/products/10862. I'm guessing they should do the trick? Granted I will be doing alot of learning before embarking on building this (I got the invetors kit to play around with first) But I just want to make sure it's even possible.

Lastly, I'm trying to figure out some electrical equations(been along time). I'm have a regulated 13.8v 10am power supply that' I'd like to bring down to 5v to possibly power the breadboard. Does this sound doable? I'm not even sure how to begin finding out the correct resistor setup to drop the voltage...

Thanks guys, and forgive my utter lack of knowledge.

I am a newbie as well(and I could be 100% wrong) but you should be using a voltage regulator to bring down the voltage, as resistors will change voltage relative to the load. See, Ohm's Law Ohm's law - Wikipedia

I don't know anything about interfacing with the web, or LCDs. Good luck with the project. Depending on the I/O requirements you might need to move beyond the chip in the Uno.

You can use a cheap 7805 three terminal regulator to bring that supply down to 5V, 1amp max–a resistor will not work for that.

Thanks guys, so you think something like https://www.sparkfun.com/products/107 will work? but you think I can only draw up to 1amp max on it? Which I can't image a relay and two LCD will need more than that.

Working backwards:
Get a switching regulator such as this to create 5v for everything.

The onboard (or any) linear regulator will run really hot with 13.8V. Amperage does not matter, parts will draw what they need.

Displays: look here and find a serial interface display. Parallel interface will use up too many pins.
If you use one with SPI interface, each will need 3 common pins: SCK, MISO, MOSI, and each a unique Chip Select pin. Nice fast interface too.

Solderless breadboard for experimenting? Perfboard for final project wiring? Not sure what you mean by breadboard.

You can find headers like arduino has, or use socket strip headers.

Depends what you want to plug in where.

Transistor with approiate resistor to trigger the motor or bell or whatever.

Ultimately doable, more a software effort than hardware.

CrossRoads, thanks for your reply, I've seen you a lot across the boards here and I really appreciate your time. Again forgive my sheer ignorance to this stuff, I'm just trying to learn this stuff.

The switching regulated your sent me too looks to be onboard aswell?

The Screens look awesome and seem like they will do the job.

The boards I chose would be standard experimental like these... Breadboard - Translucent Self-Adhesive (Red) - PRT-11317 - SparkFun Electronics. I'm guessing If I get all 5volt components there will be no need for any resistors etc.

Thanks

The regulator I mentioned will have a maximum of 1 amp in that device package. The one crossroads mentioned will have a max of 1.5 amps. Either one will work, but the 7805 is cheaper and can be purchased at every radio shack I have ever been in--so no mail order wait.

Either one will get you started.

“The switching regulated your sent me too looks to be onboard as well?”
You can mount it whereever you’d like I suppose.
There are other versions available as well.

The solderles breadboard. The sparkfun board is fine.
Or this
Solderless Breadboard 400 Points + 7m/26' Jump Wire - dipmicro electronics they have others also
and a package or 2 of these
Jumper Male/Male Wire 75pc for Solderless Breadboard - dipmicro electronics

This is what I have, 3 protoboards on a clipboard with a duemilanove bolted (#4-40 screw, nut, nylon washers) at the end.

I like the clipboard! I ordered several of the DC/DC converters from Digikey. Are they pretty similar in size to 7805's?

Thanks. Clipboard works well.

DC/DC is same width, 3 pins, just thicker.