here's a better description of what's going on...
The first step of the process removes all metadata from the file, including load addresses, all section information, any sections not marked LOAD or ALLOC, start address info, etc... What remains is a bare binary file containing what would have been loaded into memory, basically a memory image.
The second step takes that binary memory image and slaps on an elf header -- at the /beginning/ of the file so that the serial loader can load it. It just creates a new elf file with a huge data section whose contents are the loadable portion (including executable code) of the old elf file. The parameters for Tdata and Ttext tell the linker where to put this section in the new elf file, and where the start address should be, respectively.
So, if the old elf file's first loadable section (marked LOAD or ALLOC) was at 0x200c0000 and the start address was at 0x200c0000, then the parameters for Tdata and Ttext would be 0x200c0000 and Tdata would also be 0x200c0000.
See the binutils manuals at
http://sources.redhat.com/binutils/docs-2.12/ for more information.
mt