[SOLVED] Use ld to output flat binary for real mode

[person4268]

I basically want to use ld to output as a flat binary that I can use in real mode. I mostly want to do this so that I can use C for my second stage bootloader. Here is my linker script heavily based off of(mostly copied) it's page on the OsDev Wiki:

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ENTRY(start)
STARTUP(bootldr_s2.s.o)
OUTPUT_FORMAT("binary_i386?") /* Biggest isue here */ 
SECTIONS
{
  .text.start (_KERNEL_BASE_) : { /* I change this to 0x0000, right? */
    bootldr_s2.s.o( .text )
  }

  .text : ALIGN(0x1000) {
_TEXT_START_ = .;
    *(.text)
_TEXT_END_ = .;
  }

  .data : ALIGN(0x1000) {
_DATA_START_ = .;
    *(.data)
_DATA_END_ = .;
  }

  .bss : ALIGN(0x1000) {
_BSS_START_ = .;
    *(.bss)
_BSS_END_ = .;
  }


}

My biggest issue here is that I don't know what I should put as the output format. If i use "binary", it gives me this:

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ld: skipping incompatible bootldr_s2.s.o when searching for bootldr_s2.s.o
ld: cannot find bootldr_s2.s.o

Note that bootldr_s2.s was compiled with

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nasm -f elf -o bootldr_s2.s.o

and that it's currently

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    BITS 16
    start:
        mov eax, 0xBCAF ;If this is in eax, then the code loaded
        jmp $

I'm not really sure where to go from here, and would really appreciate some help.

[alexfru]

Check out Smaller C.

[GeGuNa]

ENTRY(start)
STARTUP(bootldr_s2.s.o) // set startup file (bootldr_s2.s.o)
OUTPUT_ARCH(i386) // set arch = i386 (32 bit ) / or i386:x86-64 (64 bit) / ia64 (for ia 64 arch)
OUTPUT_FORMAT("binary") // set output type (elf32-i386 / elf32-x86-64 / elf64-x86-64 / pe-i386 / pe-x86-64 / binary )

[iansjack]

If you have a single input file, and want bin format output, why are you using elf files and the linker? Nasm can output a bin file directly.

[person4268]

I know that nasm can output a flat binary file, but I'm linking so that I can use C once I get this working.

[person4268]

I should also mention that GeGuNa's answer worked. Thanks for all the help!