current community

your communities

more stack exchange communities

Stack Exchange
tour help
Take the 2-minute tour ×
Arduino Stack Exchange is a question and answer site for developers of open-source hardware and software that is compatible with Arduino. It's 100% free, no registration required.
up vote 2 down vote favorite

I bought a few atmega328p chips but unfortunately they came with the Arduino bootloader and they are set to use the external clock. I want to reset their fuses using avrdude so I can use the internal 8mhz clock but it's not working. How can I (if even possible) reset their fuses using the Arduino? I have no other programmer and here are the arguments I use for avrdude as well as the response:

avrdude -C .\avrdude.conf -p m328p -c arduino -P \\.\COM12 -b 115200 -U lfuse:w:0x62:m -U hfuse:w:0xd9:m -U efuse:w:0xff:m

Response:

avrdude.exe: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.00s

avrdude.exe: Device signature = 0x1e950f
avrdude.exe: reading input file "0x62"
avrdude.exe: writing lfuse (1 bytes):

Writing |  ***failed;  
################################################## | 100% 0.06s

avrdude.exe: 1 bytes of lfuse written
avrdude.exe: verifying lfuse memory against 0x62:
avrdude.exe: load data lfuse data from input file 0x62:
avrdude.exe: input file 0x62 contains 1 bytes
avrdude.exe: reading on-chip lfuse data:

Reading | ################################################## | 100% 0.00s

avrdude.exe: verifying ...
avrdude.exe: verification error, first mismatch at byte 0x0000
             0x62 != 0x00
avrdude.exe: verification error; content mismatch

avrdude.exe: safemode: lfuse changed! Was 62, and is now 0
Would you like this fuse to be changed back? [y/n]
share|improve this question

1 Answer 1

up vote 2 down vote accepted

You cannot set the fuses using the Arduino bootloader, since they cannot be self-programmed. You must use either serial or parallel programming via ArduinoISP or an external programmer to set them. Since the chip is configured to use an external crystal you must either connect a crystal up to the chip appropriately (see sections 9.3 or 9.4 of the datasheet) or use parallel programming. You will then be able to use the lfuse, hfuse, and efuse memory types to read and write the fuse bytes.

share|improve this answer
    
This solved it thanks. –  Anomaly May 24 '14 at 23:50
1  
If your answer includes information that mine doesn't then you should consider leaving it so that others can learn from it. –  Ignacio Vazquez-Abrams May 24 '14 at 23:56
    
It's pretty much the same answer haha –  Anomaly May 25 '14 at 0:03

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.