Hello arduinofolks!
I'm trying to burn a bootloader to an atmega328p-pu(yes it says p-pu on the chip) via an arduino uno as ISP.
ISP sketch loads perfectly to the arduino.
Then I hook up the atmega like the minimum config. In the arduino tutorial.
BUT I keep the arduinos original atmega on the arduino uno and I don't have a crystal so I skip that. I try to burn bootloader with arduino software 1.0.1 with both arduino uno and "ATmega328 on a breadboard (8 MHz internal clock)" checked in the boardmenu.
I then try the newest arduino software and do the same thing but just gets the error message saying:
"avrdude: Yikes! Invalid device signature.
Double check connections and try again, or use -F to override
this check."
I then try to change signature in case it happened to be an atmega-pu but it didn't work.
What to do?
Thanks for the help!
Dude, your post is not very clear, please go slowly and repost, but here are some comments.
The -PU suffix simply designates a DIP package, like the socketed 28 pin on the Uno.
A 328P is a 328P regardless of the package. There is also a plain 328, which would be labeled 328-PU for the DIP socket.
If you don't have a crystal, you must change the fuses.
Post the detailed error to show the signature it reports.
You have to have a crystal.
[edit] Read this tutorial by Nick Gammon: Gammon Forum : Electronics : Microprocessors : How to make an Arduino-compatible minimal board
You might need a crystal for the target chip before you can even change the fuses.
Thanks for your replies! And I'm sorry for the unclear post I'll try to clearify it.
1, I have an atmega328p-pu and the seller didn't say if a bootloader was burned or not.
2. So I want to burn a bootloader to the atmega with arduino as ISP.
3.I upload the ISP sketch to my arduino UNO, no problems.
4. I connect my UNO and the atmega like this but leave the original unos atmega on the arduino. 
5. I try to burn the bootloader in two different arduino IDEs(1.0.1 and the newest one) with both the boardoption "Arduino uno" and "ATmega328 on a breadboard (8 MHz internal clock)"
6. In both cases I get this error:
avrdude: Yikes! Invalid device signature.
Double check connections and try again, or use -F to override
this check.
- I read that if it's a plain atmega328 you have to change the signature arduino expects from the atmega, I try that, doesn't work.
- Okay I need a crystal, is there a workaround if you don't have one? As you mentioned Pegwatcher, D9 from my arduino to pin9 on the atmega?
Thanks once again, you guys rock!
Yes, you seem to have a handle on it. BUT you must use the revised version of the programmer sketch (Atmega_Board_Programmer) that you will find a link to on Gammon's site. This revised sketch puts out that 8 MHz clock on pin 9. Just follow Gammon's instructions. It works!
I beg your pardon, Archelon, that piece of code is already in the Atmega_Board_Programmer that comes with the IDE. At least, it is in the sketch that came with my IDE 1.0.6
I didn't realize that.
So you should already have that 8 MHz clock output available.
The relevant code snippet in setup():
// set up Timer 1
TCCR1A = _BV (COM1A0); // toggle OC1A on Compare Match
TCCR1B = _BV(WGM12) | _BV(CS10); // CTC, no prescaling
OCR1A = 0; // output every cycle
Gave the atmega the 8Mhz signal from the arduino according to gammons tutorial and everything went fine! Thanks for the help guys! You know these things 
Forward towards other solutions!