Device signature = 0xffffff after fuse programming

Using Arduino Microcontrollers
1

Hello

Strange problem.

I read this:

avrdude: Version 6.0.1, compiled on Dec 16 2013 at 17:26:24
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2009 Joerg Wunsch

System wide configuration file is "/usr/local/CrossPack-AVR-20131216/etc/avrdude.conf"
User configuration file is "/Users/sylvainweber/.avrduderc"
User configuration file does not exist or is not a regular file, skipping

Using Port : /dev/cu.usbmodem12341
Using Programmer : arduino
Overriding Baud Rate : 19200
AVR Part : ATmega328P
Chip Erase delay : 9000 us
PAGEL : PD7
BS2 : PC2
RESET disposition : dedicated
RETRY pulse : SCK
serial program mode : yes
parallel program mode : yes
Timeout : 200
StabDelay : 100
CmdexeDelay : 25
SyncLoops : 32
ByteDelay : 0
PollIndex : 3
PollValue : 0x53
Memory Detail :

Block Poll Page Polled
Memory Type Mode Delay Size Indx Paged Size Size #Pages MinW MaxW ReadBack

eeprom 65 20 4 0 no 1024 4 0 3600 3600 0xff 0xff
flash 65 6 128 0 yes 32768 128 256 4500 4500 0xff 0xff
lfuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
hfuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
efuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
lock 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
calibration 0 0 0 0 no 1 0 0 0 0 0x00 0x00
signature 0 0 0 0 no 3 0 0 0 0 0x00 0x00

Programmer Type : Arduino
Description : Arduino
Hardware Version: 2
Firmware Version: 1.18
Topcard : Unknown
Vtarget : 0.0 V
Varef : 0.0 V
Oscillator : Off
SCK period : 0.1 us

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.01s

avrdude: Device signature = 0x1e950f
avrdude: safemode: lfuse reads as 62
avrdude: safemode: hfuse reads as D9
avrdude: safemode: efuse reads as 7

avrdude: safemode: lfuse reads as 62
avrdude: safemode: hfuse reads as D9
avrdude: safemode: efuse reads as 7
avrdude: safemode: Fuses OK (H:07, E:D9, L:62)

avrdude done. Thank you.

After I would like to put Lfuse to OxFF

I did that:

iMac-:~ abc$ avrdude -c arduino -p m328p -P /dev/cu.usbmodem12341 -U lfuse:w:0xff:m

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.01s

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

Writing | ################################################## | 100% 0.06s

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

Reading | ################################################## | 100% 0.02s

avrdude: verifying ...
avrdude: 1 bytes of lfuse verified

avrdude: safemode: Fuses OK (H:07, E:D9, L:FF)

avrdude done. Thank you.

All seems to be ok but:

iMac-:~ abc$ avrdude -c arduino -p m328p -P /dev/cu.usbmodem12341 -b 19200 -v

avrdude: Version 6.0.1, compiled on Dec 16 2013 at 17:26:24
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2009 Joerg Wunsch

System wide configuration file is "/usr/local/CrossPack-AVR-20131216/etc/avrdude.conf"
User configuration file is "/Users/sylvainweber/.avrduderc"
User configuration file does not exist or is not a regular file, skipping

Using Port : /dev/cu.usbmodem12341
Using Programmer : arduino
Overriding Baud Rate : 19200
AVR Part : ATmega328P
Chip Erase delay : 9000 us
PAGEL : PD7
BS2 : PC2
RESET disposition : dedicated
RETRY pulse : SCK
serial program mode : yes
parallel program mode : yes
Timeout : 200
StabDelay : 100
CmdexeDelay : 25
SyncLoops : 32
ByteDelay : 0
PollIndex : 3
PollValue : 0x53
Memory Detail :

Block Poll Page Polled
Memory Type Mode Delay Size Indx Paged Size Size #Pages MinW MaxW ReadBack

eeprom 65 20 4 0 no 1024 4 0 3600 3600 0xff 0xff
flash 65 6 128 0 yes 32768 128 256 4500 4500 0xff 0xff
lfuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
hfuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
efuse 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
lock 0 0 0 0 no 1 0 0 4500 4500 0x00 0x00
calibration 0 0 0 0 no 1 0 0 0 0 0x00 0x00
signature 0 0 0 0 no 3 0 0 0 0 0x00 0x00

Programmer Type : Arduino
Description : Arduino
Hardware Version: 2
Firmware Version: 1.18
Topcard : Unknown
Vtarget : 0.0 V
Varef : 0.0 V
Oscillator : Off
SCK period : 0.1 us

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.01s

avrdude: Device signature = 0xffffff (retrying)

Reading | ################################################## | 100% 0.01s

avrdude: Device signature = 0xffffff (retrying)

Reading | ################################################## | 100% 0.01s

avrdude: Device signature = 0xffffff
avrdude: Yikes! Invalid device signature.
Double check connections and try again, or use -F to override
this check.

avrdude done. Thank you.

Of course I put an Xtal 16MHz with 2x22pF to GND on pin 9,10

I tried with 3 different AT328 P-PU all got the same result... I also changed Xtal

Why???

2

Please explain - why are you getting away from the Uno standard settings?
uno.bootloader.low_fuses=0xff >> 62 from 1111 1111 to 0101 0010
Changes several things:
CKDIV8(4) 7 Divide clock by 8 0 (programmed)
CKOUT(3) 6 Clock output 1 (unprogrammed)
SUT1 5 Select start-up time 1 (unprogrammed)(1)
SUT0 4 Select start-up time 0 (programmed)(1)
CKSEL3 3 Select Clock source 0 (programmed)(2)
CKSEL2 2 Select Clock source 0 (programmed)(2)
CKSEL1 1 Select Clock source 1 (unprogrammed)(2)
CKSEL0 0 Select Clock source 0 (programmed)(2)

uno.bootloader.high_fuses=0xde >>07 from 1011 1110 to 0000 0111
Changes all kinds of stuff:
RSTDISBL(1) 7 External Reset Disable 1 (unprogrammed)
DWEN 6 debugWIRE Enable 1 (unprogrammed)
SPIEN(2) 5 Enable Serial Program and Data Downloading 0 (programmed, SPI programming enabled)
WDTON(3) 4 Watchdog Timer Always On 1 (unprogrammed)
EESAVE 3 EEPROM memory is preserved through the Chip Erase 1 (unprogrammed), EEPROM not reserved
BOOTSZ1 2 Select Boot Size 0 (programmed)(4)
BOOTSZ0 1 Select Boot Size 0 (programmed)(4)
BOOTRST 0 Select Reset Vector 1 (unprogrammed)

uno.bootloader.extended_fuses=0x05 >> D9 = xxxx x001, changes brown out detection level

I think changing bits 7 and possibly 5 in the High Fuse byte are what's causing the problem.
With Reset disabled, you cannot get back into programming mode anymore, see 14.3.2 of the data sheet:

RESET, Reset pin: When the RSTDISBL Fuse is programmed, this pin functions as a normal I/O pin, and the
part will have to rely on Power-on Reset and Brown-out Reset as its reset sources.

Thus a programmer cannot hold Reset low to get the part into programming mode.
You will have to resort to High Voltage (12V) Programming to recover the chip.
There's a nice write up here by Nick Gammon (easier to follow vs 28.7 of the datasheet):

3

He changed the low fuse to 0xFF. I think you're being confused by the avrdude bug that swaps what it shows for high an ext fuse at the bottom line.

4

potzli,

Try low fuse as F7 - full swing crystal. That makes it less susceptible to noise.
Do you have decoupling caps on your device if it's a home made setup?