Newbie question - firmware backup

I have Melzi 2.0 board with Repetier firmware version 0.91 (probably).
I want to install induction sensor for bed leveling.
However, all the comments from the configuration.h and all the other files are removed.
Therefore I'd like to install either newer version of Repetier firmware or some other firmware (like Marlin) and configure it.
To stay safe, I'd like to backup the current firmware somehow.
I have some USBasp mini programmer, however I have no idea if and how can I backup the binary file from the ATmega chip.
Can anyone suggest how to proceed?

Thanks!

Use arvdude (command line only) (is part of Arduino IDE, but will not be in the path)

eg
avrdude -c usbasp -b 38400 -i 10 -p m1284p -P /dev/ttyUSB0 -U flash:r:factory.hex:i

-c is the type of programmer you have probably usbasp or usbasp-clone
-b baud rate
-p is the processor either m644p or m1284p depends what your board has.
-P is the com port /dev/ttyUSB0 is a linux example, com3 for a windows eg.
-U memtype : operator : filename[:format] in this case flash ROM firmware, read to file factory.hex in Intel Hex format. You might also want to dump your eeprom

See [www.nongnu.org] for more details

Edited 1 time(s). Last edit at 01/25/2016 09:30PM by Dust.

Thanks a lot! This is what I wass looking for. Now I have the insurance

For newbies like me: reading the EEPROM is done using the same simple command, but with the last parameter
-U eeprom:r:backup.eep

Thanks again for the info.

Did you get your Melzi V2.05 controller board updated? What IDE did you use and what type of ISP programmer did you use? Thanks