I am considering purchasing these ATmega328 s from 3 pack ATmega328P.

The company says they come with the Arduino UNO bootloader. I do NOT have any 16 MHz crystals, and I would like to make the chips run on the 8 MHz internal crystal.

I have an Arduino Duemilanove.

Is it possible to burn the minimal setup bootloader from here onto the bootloaded chips without using a crystal?

  • Have you looked at the datasheet yet? May 8, 2016 at 3:50
  • I'm not sure how much that would help. In the minimal setup description they say the chip will not work when burned with the external crystal bootloader until a crystal (i do not have one) is connected. I was wondering if this applies to bootloader burning as well
    – T Williams
    May 8, 2016 at 4:13
  • Why do you consider buying ATmega with Arduino bootloader if you don't need Arduino bootloader? I'm sure you can finder cheaper sets without any bootloader at all.
    – jfpoilpret
    May 8, 2016 at 8:05

1 Answer 1


I've done just that on a Arduino Pro Mini of mine.

You need to change the fuses to have the chip use the Internal Oscillator, instead of a crystal. After that you just program the 8-MHz version of the bootloader. Like the one used in the Arduino Pro Mini 3.3V.

The only problem is that you need to connect a crystal, to change the fuses to not use the crystal. Though it doesn't need to be 16Mhz. Anything between 1 and 16MHz will do.

But since you need to change both the fuses and the bootloader, there is no advantage to buy chips with the bootloader preinstalled.

I'd just buy some bare chips without the bootloader.

PS $4.66 is on the high side for an ATMega328P-PU.

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