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Comments:
<0> or something
<1> variablename: .byte 0
<0> cool :)
<1> .short for dw
<0> jmp short still the same?
<1> .int for dd
<1> jmp short is simply 'jmp'
<0> 8bit = b 16bit = short, 32bit = int
<0> gotcha
<1> i never found a way to force as to emit short jump
<1> but it seems to do it automatically anyway
<0> nop still the same
<1> nop is nop
<0> cool
<0> :P Srory
<0> just, im new
<0> lol
<0> with As
<0> what about :
<1> also, .quad is 64-bit number, in case you ever need it in a bootloader...
<0> times($$-$) db 0
<0> alrighty
<1> times($$-$)? what is that?
<0> padding
<1> to what position?
<0> well
<0> to make the bootloader exactly 512 bytes
<0> eg:
<0> times 510-($-$$)dbx00
<0> dw 0xAA55
<1> ah.
<1> then, supply a label [like, start:] at the beginning
<0> also, I know bits 16 in gas is .code16
<0> but whats the equivalent of [org] directive?
<1> and do .org start+510
<0> ?
<1> [org]? there's no org.
<1> linker deals with that
<0> what does .org start+510
<1> it skips enough bytes to make current position == start+510
<1> or, in other words, it pads to 510 bytes since start
<1> as .org is very different from nasm [org]
<0> okay
<0> As is crazy
<1> it isn't
<1> it just wasn't designed to be used by humans
<0> lol
<0> how about this?
<0> bpb_vendor_iddb"MSDOS5.0"
<0> .bpb_vendor_id .byte ???
<1> bpb_vendor_id: .ascii "MSDOS5.0"
<1> careful to use .ascii and not .string
<0> gotcha
<0> why?
<1> .string adds the trailing \0 for C strings
<1> and so does .asciz
<0> ah
<0> also, btw
<0> can I have numbers as hex?
<0> like
<0> bla: .short 0xFFF
<1> sure
<0> cool :D
<1> as understands numbers the same way that C does
<1> so careful, cause everything starting with 0 is an octal number
<0> ...
<0> so, 0xAB
<0> isnt hex?
<1> 0xAB is hex
<0> what about
<0> 01 ?
<1> it's 01 in octal
<0> gotcha
<1> 10 is decimal [0xa]
<1> 010 is octal [0x8]
<0> so...
<0> ident .ascii "Blablabla"
<0> ?
<1> ident: .ascii "Blablabla"
<1> note the :
<0> ah
<0> ?
<0> ahhh
<0> gotcha
<0> what about JMP $
<0> ?
<1> wtf is jmp $ and why would you want to use it?
<1> anyway... 'jmp .' it is
<0> jmp $= jmp over and over forever.
<0> I still have no idea how to padd from the end of the file, so its a perfect 512b
<0> lol
<0> pity me :P
<0> lol
<1> jmp .
<1> pad? add a 'start:' label at the start of bootloader
<1> then, at the end:
<1> .org start+510
<1> .short 0xaa55
<0> hey, why is it bitching at me about having _s in my variable names?
<0> eg :
<0> this_is_a_byte: .byte 0
<1> humh? this ***embles fine here.
<0> ...
<0> okay, do I need ot say anythign?
<0> do I have to place them naywhere special?
<0> it thinks they are mnemonics
<0> I just have : fbpb_vendor_id: .ascii "MSDOS5.0"
<0> for example
<1> it works
<1> at least for me
<0> mannn
<0> ive got this
<0> .bpb_data:
<0> then I have all the stuff
<0> like
<0> .fbpb_bytes_per-sector: [TAB] .short [TAB] 0x200
<0> without the start5ing .
<1> um
<1> don't start labels with '.'
<0> man this is painful
<0> why?
<1> as could think it's a directive
<0> ah, thats true
<0> slowly getting the hand of it, thank you for your help so far Mwk
<0> how big is di?
<0> 16bit?
<1> di is 16 bit
<1> edi is 32-bit
<1> also, it's %di, not di
<0> yeah
<0> push = pushl ?
<0> is the XOR mneomnic still the same toobtw?
<0> er in 16bit, wont we want to use pushw ?
<0> wb ronny
<2> damn - nettalk is a scarry irc client
<2> makes noises on highlight
<2> btw - im on windows now
<1> push == pushw
<1> xor == xorb for 8-bit, xorw for 16-bit, xorl for 32-bit
<0> what about err...
<0> like ...
<0> mov bx, [variable] === movw (variable), %bx ?
<1> movw variable, %bx
<0> why not ()s?
<1> because at&t is brain-damaged
<1> taking address of variable, otoh, would be movw $variable, %bx
<1> careful, cause the same applies to number
<1> movw 0, %ax
<1> this one takes value from *address* 0 and puts it in ax
<0> ...
<1> movw $0, %ax
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