Just the ATMega!

Hello, there! I've seen people talking about them simplifying their boards to just the ATMega, an oscillator, and a regulator, such as in this article:

http://linux-utils.blogspot.com/2010/12/preparing-arduino-bug-zapper.html

That really interests me, but then how do I program it while still keeping the familliar functions of that arduino environment? I know I have to buy the chip with the bootloader, but I don't know where to go after that.

So, the question:

How do I interface just the chip and oscillator with my computer for programming?

Thanks in advance! 8-)

Doo a forum search for arduino standalone .

Get an FTDI to serial cable with the 5-pin connector, like this:

http://www.google.com/products/catalog?q=ftdi+cable&um=1&ie=UTF-8&cid=13412712673349640211&ei=wPgOTdD7H4r6sAOU5IybDw&sa=X&oi=product_catalog_result&ct=result&resnum=4&ved=0CDkQ8wIwAw#

It takes the place of the USB jack and FTDI chip in a full dress Arduino.

You might like to try the step by step guide to building a perfboard standalone arduino at musheen.com.

Perfboard Standalone Arduino II

I know I have to buy the chip with the bootloader, but I don't know where to go after that.

Actually, you don't even need a bootloader. Bring out the ICSP (In Circuit Serial Programmer) header pins to somewhere on the board. Then use a ICSP programmer to program it.

Don't have one? Use the Arduino:

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1165363464

The ICSP header (the 6-pin male header on the Arduino) is how you put a bootloader onto the Arduino:

http://www.arduino.cc/en/Hacking/Bootloader

By using it, you bypass the need for a bootloader (and gain the program space used by the bootloader, incidentally). The only reason the Arduino isn't set up like this from the beginning is that it would require you to own a programmer (which vary in price from cheap to expensive), and the developers of the Arduino wanted it to work "out of the box", so the bootloader and USB connection was the choice.

But once you have a working Arduino, coupled with the sketch (which is included in your sketch sample folder) - you can use it to upload your own bootloader onto bare ATMegas (if you're into customizing bootloaders), or just upload your code directly, bypassing the bootloader step.

:)