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Topic: Writing a howto (Read 662 times) previous topic - next topic

MartinH

Hi
I'm working on a project with the ATMEGA 328, building it up using the Arduino UNO, transferring it to a raw ATMEGA on a standalone board
As I walk through the project I had to tackle a lot of forums and threads because the one truth that solves my problem at hand is covered in one post out of "hundrets" of posts and threads.
This in turn burned up lots of hours, just to find THE ONE information.

Thus I'd like to write a condensed howto, directed to newbees, which covers all these obstacles and provides (my) solutions and if necessary links to the posts I found.

The how to shall be set in three parts
- Basics on the ATMEGA and surrounding technique
- the real HowTo get Arduino code on raw ATMEGA (on Breadboard or other standalone technique)
- my own project which deals with switching AC plugs via the network.

Since I dont want to repeat a thing that is already done:
1) Does anybody know if this was already done (but i did not find it)?
2) Where is the best place to do this within the arduino community?

Thanks for your support

Martin

CrossRoads

1) numerous times. would seem you did not find it.
Condensed How To:
Wire up your project with minimum of these signals to the ATMega chip:
+5 to VCC and AVCC, GND to Gnd and AGND.
Add these Components: 16 MHz xtal, two 22pf caps, 10K reset pullup resistor, 100nF caps from VCC, AVCC, ARef and GND.
Download Optiloader sketch on to  a working arduino, connect arduino D13, D12, D11, D10, power, gnd to new device's D13,D12,D10, Reset, power, gnd:
https://github.com/WestfW/OptiLoader
See the video at the end of this thread:
http://arduino.cc/forum/index.php/topic,68183.0.html

2) post here. create a Playground article when done.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

MartinH

Hi CrossRoads,
thanks for the info on the bootloader.

I did not explicate in the technical problems because this i wanted to do in the HowTo
I wanted to omit the bootloader
As I said, one of 100ds of threads conatins the one sentence: the Bootloader also sets the fuses.
Everone knows that but a newbee..  so everyone says.. flash a pootloader.. but no one says that the fuses are set as well.
If you dont want to use a bootloader, there is one article telling U the different methods but does not say one word about how to deal with the fuses.
I thought I could omit the external xtal but as it shows in another article I found the one sentence:
UART does not work (sometimes but mostly not) when the ┬ÁC is ticked by the internal RC-Oscillator.
Although flashing the hex-file or reading the fuses via AVRDUDE is possible in the raw setup with no extrenal xtal.
Well, these experiences and background information (there is some more) I wanted to put int ONE article.

rgds
Martin

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