I built several boards with an ATMEGA328 and no crystal a couple of years ago. I programmed them successfully with a bootloader using usbasp, and with a sketch using the Arduino serial interface. I have now made some more, but I get an error message from AVRDUDE when I try to burn the bootloader:
avrdude: WARNING: invalid value for unused bits in fuse "efuse", should be set to 1 according to datasheet This behaviour is deprecated and will result in an error in future version You probably want to use 0xfd instead of 0x05 (double check with your datasheet first).
I followed the instructions here and I am using the hardware configuration archive referenced on that page: breadboard-1-6-x.zip.
If I reprogram the bootloader on a device that does have a crystal, it works if I select Arduino Pro/Pro Mini (3.3V, 8MHz), but fails with the message above if I select the breadboard specified in the boards.txt from breadboard-1-6-x.zip.
There are no other error messages, but... if I turn on verbose, it works.. turn verbose off and it stops working again. Maybe verbose mode modifies the timing enough to make it work.
I know that you can use the -B option to slow down avrdude when you run it from the command line: is there a way of doing the same thing from within the Arduino environment?