Document new Safe Mode feature and switch.

git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk/avrdude@443 81a1dc3b-b13d-400b-aceb-764788c761c2
This commit is contained in:
Eric Weddington 2005-01-24 21:26:14 +00:00
parent 70db5c5e85
commit c8f18db55e
1 changed files with 28 additions and 3 deletions

View File

@ -449,6 +449,14 @@ parallel or serial port, use this option to specify the alternate port name.
Disable (or quell) output of the progress bar while reading or writing
to the device.
@item -u
Disables the default behaviour of reading out the fuses three times before
programming, then verifying at the end of programming that the fuses have not
changed. If you want to change fuses you will need to specify this option,
as avrdude will see the fuses have changed (even though you wanted to) and
will change them back for your "saftey". This option was designed to
prevent cases of fuse bits magically changing.
@item -t
Tells AVRDUDE to enter the interactive ``terminal'' mode instead of up-
or downloading files. See below for a detailed description of the
@ -583,6 +591,8 @@ Reading | ################################################## | 100% 6.83s
avrdude: verifying ...
avrdude: 19278 bytes of flash verified
avrdude: safemode: Fuses OK
avrdude done. Thank you.
%
@ -609,6 +619,8 @@ Reading | ################################################## | 100% 46.10s
avrdude: writing output file "c:/diag flash.bin"
avrdude: safemode: Fuses OK
avrdude done. Thank you.
%
@ -623,7 +635,7 @@ fuse bytes to 0xff, 0x89, and 0x2e respectively:
@example
@cartouche
% avrdude -p m128 -U flash:w:diag.hex \
% avrdude -p m128 -u -U flash:w:diag.hex \
> -U eeprom:w:eeprom.hex \
> -U efuse:w:0xff:m \
> -U hfuse:w:0x89:m \
@ -828,11 +840,13 @@ avrdude>
@noindent
Program the fuse bits of an ATmega128 (disable M103 compatibility,
enable high speed external crystal, enable brown-out detection, slowly
rising power). First display the factory defaults, then reprogram:
rising power). Note since we are working with fuse bits the -u (unsafe)
option is specified, which allows you to modify the fuse bits. First
display the factory defaults, then reprogram:
@example
@cartouche
% avrdude -p m128 -c stk500 -t
% avrdude -p m128 -u -c stk500 -t
avrdude: AVR device initialized and ready to accept instructions
avrdude: Device signature = 0x1e9702
@ -1578,6 +1592,17 @@ Problem: I'm not using linux and my AVR910 programmer is really slow.
Solutions: The reasons for this are the same as above.
If you know how to work around this on your OS, please let us know.
@item
Problem: I cannot modify the fuse bits on my AVR!
Solution: You probably forgot to specify the -u option, which allows you to modify fuse bits.
This is done to prevent corrupt data from changing the fuse bits without you knowing about it, and
currently also prevents the user from changing the fuse bits by accident. This patch was added in
response to a number of occasions when an AVR had stopped responding because the fuse bits got changed
by an error caused by the programmer. Programmer of course meaning both the physical device, and the
person sitting at the keyboard.
@end itemize