Questions about ATMega328P powered project with Graphic LCD.

Community Projects
1

Hi,

I am working on a project which will use the [Nokia 5110 LCD.

The complete unit has to be small and power effective so I’m going to run the ATMega328P without any dev board, which is a whole new domain for me (I’ve got plenty of Arduino Uno experience). I’ve read a lot, but I can’t seem to wrap my head around all of it, so I got some questions.

  1. If I hook the ATMega328 up to a 3V source and add a 8MHz crystal, do I need to do anything on the code side differently than I would normally do on the Arduino Uno dev board?

  2. How would I upload sketches to the microcontroller? Is it possible to just do anything as usual on the Arduino Uno dev board, remove the microcontroller and put it in the project’s circuit which has the 8MHz crystal?

  3. I’ve noticed that people use two caps when having the microcontroller on a breadboard. Are those required all the time, or only when you want to upload to the microcontroller?

Thanks for any answers in advance, and I might have some follow up questions as well!](https://www.sparkfun.com/products/10168)

2

  1. No, all code is the same.

  2. If the dev board is 3.3V, you can just remove the 328 and place it in your project. You can also place ICSP pins on your project board along with the reset components then you can program it in your project.

3)The second question’s answer will depend upon what caps your are talking about… There are caps for the crystal = mandatory, caps for the reset = mandatory, and caps for decoupling = pretty much mandatory…

3

You will need an 8 MHz bootloader.

4

codlink:

  1. No, all code is the same.

  2. If the dev board is 3.3V, you can just remove the 328 and place it in your project. You can also place ICSP pins on your project board along with the reset components then you can program it in your project.

3)The second question’s answer will depend upon what caps your are talking about… There are caps for the crystal = mandatory, caps for the reset = mandatory, and caps for decoupling = pretty much mandatory…

I don’t have a 3.3V dev board, only the Arduino Uno. Would it be possible to use the Arduino Uno board to program the 3V ATMega328 with ICSP pins?

Or could I simply use [this method to convert my Arduino Uno to 3.3v and use it to program the chips? Does it not matter that the Dev board would then be 16 MHz and the actual circuit only 8 MHz?](3.3V Conversion | Arduino Tips, Tricks, and Techniques | Adafruit Learning System)