the Target Selection?

[Nick Clifton]

Hi Martin,

> I know we can use objcopy like this:
> $ objcopy -O binary xxx.elf xxx.bin
> 
> But I don't know where to find the list of format like "binary".

If by "list of format" you mean "specification of the file format of"
then the short answer is that there is none.  The "binary" file format
is just that - a straight binary image with no structures in it at all
- ie there is no header, no symbol table, no debug information etc.

This is explained in the binutils documentation (binutils.info), where
it says:

    objcopy can be used to generate a raw binary file by using
    an output target of 'binary' (e.g., use "-O binary"). When
    objcopy generates a raw binary file, it will essentially
    produce a memory dump of the contents of the input object
    file.  All symbols and relocation information will be
    discarded.  The memory dump will start at the load address
    of the lowest section copied into the output file.

Cheers
        Nick