Arduino USB PORT [SOLVED]

Hi.
I would like to know if is possible use the usb port on Uno to do some comunication with others devices instead of computer or other thing else while using a external power supply?

The UNO USB port behaves normally as a serial port.
From - http://arduino.cc/en/Main/ArduinoBoardUno - "The Uno differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it features the Atmega8U2 programmed as a USB-to-serial converter. "

There are some threads discussing reprogramming the AtMega8u2 like - Arduino Forum - but there are more (maybe playground too?)

Thanks!
Does anybody know where I can find some code examples using the USB port of Mega?

ViniciusPolo:
Thanks!
Does anybody know where I can find some code examples using the USB port of Mega?

To do what? What are you hooking up to what and how? And what for?

Anything especial.
I just have my Mega and want to learn what I can do with a USB Port for futures projects.
Can I revice input from a usb keyboard?

If you are asking if you can plug USB devices into the Mega, look at the cord. It has an end that connects to a USB port, not other USB devices.

There are USB Host shields that you can get that allow you to connect USB devices to the Arduino, and actually use them - as soon as you write the driver.

So, cant an Arduino be a USB host without shield?

So, cant an Arduino be a USB host without shield?

No.

Thanks all of you!

You can get data out of the arduino over USB, assuming you are able to open a serial interface with it (Ex. using the arduino and your computer + serial monitor in the arduino IDE). Getting other embedded devices to talk/listen over the USB connector is probably more complicated than just using the pins on the arduino board. I'm not the one who could explain how to do it, but anything you connect to your arduino via USB has to talk to the arduino similar to how your computer talks to your arduino.

Since you are just interested in learning, I recommend grabbing a book with project ideas in it. I really liked "Making things talk" by Tom Igoe, but its a little bit dated at this point (still very helpful though).

Generally though, do example projects first so you are not totally in the dark. Then once you understand how those work, you can think of other projects that you can do based off of the things you have done.

PaulS:
If you are asking if you can plug USB devices into the Mega, look at the cord. It has an end that connects to a USB port, not other USB devices.

There are USB Host shields that you can get that allow you to connect USB devices to the Arduino, and actually use them - as soon as you write the driver.

Paul I am trying to gather material on connecting a 3G USB modem to the Arduino ,do you have any knowledge on this?

I was intrigued with the following statements I found

Has anyone tried this with canadian provider SIM cards? I got it workign fine with Rogers, but I am in Saskatchewan and our provider “Sasktel” SIM cards will not even get detected by this…get SIND: 0 everytime, yet Rogers SIM works fine. I tried 4 different Sasktel Sim cards and no go.

Anything else I can try changing to get it to read these cards?

Comment by Keenan | February 9, 2011

Sasktel does not seem to offer a 2.5G GSM cellular network, only 3.5G. The GSM module used in the Sparkfun shield therefore will not work with Sasktel.
cheers
john

Comment by John Boxall | February 9, 2011

Thanks for the prompt response, sorry I should have caught that but I am just getting started. Is there another shield or cellular module that would work with 3.5G and this code?

Comment by Keenan | February 10, 2011

To be honest I have not seen a 3G GSM shield on the market. With regards to your other question, it is not the SIM card – 2G and 3/3.5G are physically separate networks, Sasktel doesn’t run a 2G network.
Looks like you’d have to use Rogers in your area.
cheers
john

Comment by John Boxall | February 10, 2011

I thought the only difference in 2.5G and 3G was the speed !