In the Troubleshooting guide, this question is answered... partly.
I have a arduino nano 168 with 16K mem. Was working perfeclty. Uploading code ect for alreadya month. Yesterday i used eclipse (which uses avr plugin -> avrdude) to upload some code. The code was more then 16K (maybe that's the problem), and the upload crashed.
Now:
The green power led is constant red.
No diff when usb powered or external.
When connecting to pc, rx and tx ligth for a milli sec and the pc recognizes the board. But after then all lights dead.
L led (pin 13 connected) always stays out. never on, not even a blink.
When pressing reset, nothing happens. All leds stay out, and power led stays red.
Can anyone tell me what has happened? It it possible to correct this?
Would i buy another one or but a programmer to reprogram the loader?
You have over written the boot loader code which is in the last 2K of memory. Therefore you need to re program it in again. There are lots of ways to do this depending on what equipment you have. You can burn it straight from the arduino environment under the tools menu if you have one of those programmers it shows there.
thanks grumpy friend, i had a feeling it was that, but read on another thread that the bootloader, which is also used to load new programs to the avr, protects itself. So that is not true.
I just bought a bootloader on eBay to test this. Give me a week to give feedback (for other which might have the same problem),
It depends on how the fuse bytes are set. In general the boot loader is not protected because it can then only be unprotected with a high voltage (12V) programmer. Therefore this option is normally unused.