Introduction: True Atmega Standalone, Running Without Crystal Oscillator (Arduino)
I recently ordered a bunch of Atmel Atmega chips, 328 to be precise and as soon as i got them i realised i was lacking some very important components to make these chips function. The 16mhz crystal and the two 22pf capacitors to accompany it. From previous knowledge of the Atmel chips i knew some of them contained internal clocks, i hoped that the atmega did to. After some research i found it was possible to run an atmega completely on its own, save power and a sketch of course.
This instructable will inform you how to run any atmegaxx8 series chip on its own.
Atmegaxx8 (doesnt matter which one but i prefer the 328)
Breadboard (circuit on bottom left is irrelevant)
LED and resistor (optional)
Step 1: Breadboard
The breadboard setup is fairly simple and requires minimal components, none at all.
I have included a resistor on pin 14 or digital pin 8, purely to test my chip.
Step 2: Computer Setup
The computer side of things consists of a few easy steps but many people seem to get the wrong folders, make sure you are sure.
Download the bootloader files from here.
Go to wherever your arduino sketchbook is and create a new subfolder titled 'hardware'.
Extract the downloaded file Breadboard.zip into the new hardware folder you created.
Restart/start you arduino programming environment and you should see in tools-boards a new entry called arduino on breadboard
Step 3: Computer-Arduino Setup
Make sure to plug in your Arduino with the breadboard setup and have the ide running when doing these steps.
Under boards select the new arduino on breadboard entry.
Under programmers set it to arduino as isp
Under examples you will find an example called 'arduino isp' upload to your board.
Under tools click burn bootloader, this can take a few minutes so dont think its not working.
When this is all complete, you should have a chip that can function like a normal arduino but without the clock.
Step 4: Uploading Sketches
There are two ways of doing this, either with an Arduino or a USB breakout board type thing.
The Arduino way is detailed in the image.
The USB way is to connect TX to RX and RX to TX between the chip and your breakout board and just upload from there.
This is where you may want and LED, just to test its working.
I also like to print out a sticker for the chip so i know which pins are which, if the one below doesn't work inbox me and ill fix it.