Standalone Arduino 3.3v: Burning bootloader error

Hi guys

Im trying to burn a bootloader on to my Arduino on a breadboard. The standalone Arduino is running 3.3v and 8 Mhz. Im using this ATmega328P-PU. I use my Arduino UNO as ISP.

The wiring between the UNO and the standalone Arduino are like shown here. (Except for the 5v to power rail connection - I use the 3.3v to power rail instead).

I have uploaded the ArduinoISP sketch to the Uno and selected "Arduino Pro or Pro Mini (3.3v, 8 Mhz) w/ ATmega328" in the board menu. I use the same port as I use to program the Uno. Last I selected "Arduino as ISP" as Programmer. But when I press "Burn Bootloader" I get this error message:

 avrdude: verification error, first mismatch at byte 0x0000
          0xda != 0x00
 avrdude: verification error; content mismatch

What am I doing wrong?

Thanks a lot! :slight_smile:

First, there's a problem. You are powering your standalone with 3V3, yet the other pins are working at 5V (Arduino UNO works at 5V). When you put higher voltage than Vcc on arduino pins they can get damaged, not confirmed though, I hope not.

Second, is it a brand new chip or did it use another configuration before? Because it's important to check if it needs an external osc to be programmed or not.

You know there's not difference on Arduino pro mini 3v3 or 5V besides the voltage supply. Thus, you shuld burn Arduino Pro or Pro Mini (3.3v, 8 Mhz) powering it with 5V supply (disconnect all other devices).

Once programmed with 5V you can run your stanalone at 3v3.

I agree with mart256, you can use the 8MHz on 3.3V, but also on 5V as well. But you still have to select the 3.3V 8MHz Pro Mini when burning the bootloader.

When 0x000 is returned, perhaps the wires are not connected properly.
Can you check your wiring once more ? Perhaps the breadboard has a few bad contacts.
Could you add a 100nF decoupling capacitor at 5V and GND near the ATmega chip ?
Do you have bunch of ATmega328P chip ? Perhaps this one is damaged.