I am working on a project that will eventually use a stand alone arduino. It needs to communicate to the PC via USB. Do I need a seperate chip to handle these communications or can I just connect the USB data pins to pins 0 and 1 on the atmega?

Note: I can easily program it with the arduino uno that is not a issue. But the program needs USB input and output to run.

 

You cannot connect the TX/RX on the arduino to USB directly but there are "USB to Serial" adapters available cheaply on ebay etc. You then connect TX/RX to the adapter and then connect that to the USB on your PC.

I think it is typically better to use one of these than to put an FTDI chip on your standalone board since it will consume power and add complexity that you don't need.

<edit>
Of course what I meant to write was:
You cannot connect the TX/RX on the ATMega to USB directly

 

I worked with Arduino Due board, it has USB. I simply plugged Due to pc using USB cable (follow driver installation instructions), it worked fine and I had no trouble sending data from Due to pc.

UNO has USB already.



From UNO website:
http://arduino.cc/en/Main/ArduinoBoardUno

"An ATmega16U2 on the board channels this serial communication over USB and appears as a virtual com port to software on the computer."

"The Arduino software includes a serial monitor which allows simple textual data to be sent to and from the Arduino board."

 

So something like this: http://www.amazon.com/gp/offer-listing/B00K43Q912/ref=dp_olp_new?ie=UTF8&condition=new ?

Thanks!

 

So something like this: http://www.amazon.com/gp/offer-listing/B00K43Q912/ref=dp_olp_new?ie=UTF8&condition=new ?

Thanks!

Did you see shteil01's post? The Arduino UNO has USB built in and can talk to a PC over USB directly, without the need for adapters.

 

Yes I did. In my original question and title it says stand alone arduino so that means just the atmega chip not the whole arduino uno. Why pay for a whole new uno when you can get an atmega chip for a couple bucks.

 

Ahh. Terminology confusion. To me, Arduino is a system and an Atmega is a microcontroller. Hence, I personally think that a standalone Arduino doesn't exist. I'd use "Atmega" instead. To each his own.

 

Ok, so you are just going to use ATmega328 chip.

 

So something like this: http://www.amazon.com/gp/offer-listing/B00K43Q912/ref=dp_olp_new?ie=UTF8&condition=new ?

Thanks!

Yes but I tried one of those cables but it seemed a bit flakey, I prefer the little boards like this:
http://r.ebay.com/iJfpAK

 

Yes but I tried one of those cables but it seemed a bit flakey, I prefer the little boards like this:
http://r.ebay.com/iJfpAK

I saw a tutorial about stand alone ATMega328, they said if you use cable, then you need a couple transistors and resistors to interface the cable to the ATMega328.

This one here: http://www.hobbytronics.co.uk/arduino-atmega328-hardcore

They explain how to use the little board you linked and how to use USB to serial cable.

 

Alright. Thanks!

 

I use these guys, with cheap Asian clones appearing on ebay occasionally for a couple of bucks. http://www.mattairtech.com/index.php/featured/mt-db-x4.html.