Atemega 328p bootloader

Hi,

I'm making a project with atmega328p-AU with a package TQFP and i programmer it through arduino ISP. I burned the bootloader of atmega328p 16MHz(because i used xtal 16Mhz on PCB) and i already programming it but the idea is working without the xtal. So, i removed the xtal and burn bootloader of atmega328p 8Mhz internal clock and the system worked fine. i made some tests with and without to optimize my project but one time i burn the bootloader atmega328p 8Mhz internal clock and appears this error:

avrdude: Yikes! Invalid device signature.
** Double check connections and try again, or use -F to override**
** this check.**
Erro ao gravar o bootloader.

After that, i can't burn any bootloader or upload any sketch.

Someone can help me?

Does the speed expected by the bootloader match the clock speed you are presently using?

I think so. the strange thing is that the system worked well with the two frequencies (16MHz and 8MHz) and suddenly doesn't work with any frequency.

I didn't change the speed because bootloader does that. With one bootloader the clock is set with 16MHz by xtal and the other the clock is set with 8MHz by internal clock.

I'm little bit confused with your post. Anyway, the bootloader requires some clock frequency. It is defined during its build process and must fit to MCU's clock frequency. Internal or external clock use is defined by fuses and it has no direct relation with the bootloader. If you've removed the crystal and didn't change the fuses for internal crystal before, then the MCU will not start.

Please, post detailed output from the error (switch it on in preferences).

One bootloader is to atmega works with external crystal 16MHz and the other is to atmega works with internal oscillator 8MHz. the uC worked with both but now doesn't work and i can't burn any bootloader or upload any code.

the error is:

avrdude: Yikes! Invalid device signature.

Double check connections and try again, or use -F to override this check.

Erro ao gravar o bootloader. (error burn the bootloader).

the atmega simply doesn't work, if the problem were in fuses i think the atmega had not work any time.

someone had a problem like this?

Provide more detailed info from the output. Invalid device signature, ok, but what is the actual signature. Go to the preferences and check out the box "Show verbose output during upload". Try to upload once again and provide the output.