It is warning you that you are changing the low fuse settings. This is because changing fuses can permanently damage the chip.
In this case it looks like the existing fuse settings are CKSEL1 only, but your AVRDude command wants to set 0x05, which enables a bunch of fuses. You should be ok setting them to factory defaults. I don't have my Makefile handy, but I think I use 0x62 or 0x05, which is suitable for any bootloader (and thus suitable for AMForth.) Here is a good reference: https://www.instructables.com/id/How-to-change-fuse-bits-of-AVR-Atmega328p-8bit-mic/ There are online tools to generate fuse values: http://www.engbedded.com/fusecalc Every time I run into this I have to recheck my notes, which is why I save the values in the Makefile. I've yet to blow up a 328P with fuses, but I suppose it can be done. I'll respond with my Makefile snippet and rationale later if it looks like it will help. On Tue, Oct 16, 2018, 14:56 Jan Kromhout <krom1...@hotmail.com> wrote: > When loading AmForth into my Arduino Uno I get an error on the end. > My question is what to do in that case? > Are my settings of the fuse one? > > Cheers, > > Jan > > > avrdude: verifying ... > avrdude: verification error, first mismatch at byte 0x0000 > 0xfd != 0x05 > avrdude: verification error; content mismatch > > avrdude: safemode: efuse changed! Was 5, and is now fd > Would you like this fuse to be changed back? [y/n] n > avrdude: safemode: Fuses OK (E:05, H:DE, L:FF) > > My question is what to do in that situation? > > > > > > MacBook-Pro-van-Jan-5:avrdude jankromhout$ avrdude -P > /dev/tty.usbmodem00230362 -c avrispv2 -b 19200 -p m328p -e -U > flash:w:uno.hex:i -U eeprom:w:uno.eep.hex:i -U efuse:w:0x05:m -U > hfuse:w:0xD9:m -U lfuse:w:0xFF:m > > avrdude: AVR device initialized and ready to accept instructions > > Reading | ################################################## | 100% 0.00s > > avrdude: Device signature = 0x1e950f (probably m328p) > avrdude: erasing chip > avrdude: reading input file "uno.hex" > avrdude: writing flash (32638 bytes): > > Writing | ################################################## | 100% 2.06s > > avrdude: 32638 bytes of flash written > avrdude: verifying flash memory against uno.hex: > avrdude: load data flash data from input file uno.hex: > avrdude: input file uno.hex contains 32638 bytes > avrdude: reading on-chip flash data: > > Reading | ################################################## | 100% 1.86s > > avrdude: verifying ... > avrdude: 32638 bytes of flash verified > avrdude: reading input file "uno.eep.hex" > avrdude: writing eeprom (144 bytes): > > Writing | ################################################## | 100% 0.06s > > avrdude: 144 bytes of eeprom written > avrdude: verifying eeprom memory against uno.eep.hex: > avrdude: load data eeprom data from input file uno.eep.hex: > avrdude: input file uno.eep.hex contains 144 bytes > avrdude: reading on-chip eeprom data: > > Reading | ################################################## | 100% 0.02s > > avrdude: verifying ... > avrdude: 144 bytes of eeprom verified > avrdude: reading input file "0x05" > avrdude: writing efuse (1 bytes): > > Writing | ################################################## | 100% 0.01s > > avrdude: 1 bytes of efuse written > avrdude: verifying efuse memory against 0x05: > avrdude: load data efuse data from input file 0x05: > avrdude: input file 0x05 contains 1 bytes > avrdude: reading on-chip efuse data: > > Reading | ################################################## | 100% 0.00s > > avrdude: verifying ... > avrdude: verification error, first mismatch at byte 0x0000 > 0xfd != 0x05 > avrdude: verification error; content mismatch > > avrdude: safemode: efuse changed! Was 5, and is now fd > Would you like this fuse to be changed back? [y/n] n > avrdude: safemode: Fuses OK (E:05, H:DE, L:FF) > > avrdude done. Thank you. > > MacBook-Pro-van-Jan-5:avrdude jankromhout$ > > _______________________________________________ > Amforth-devel mailing list for http://amforth.sf.net/ > Amforth-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/amforth-devel > _______________________________________________ Amforth-devel mailing list for http://amforth.sf.net/ Amforth-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/amforth-devel
