bkerndev 16kb+ problem

[Martius]

I placed extern in front of them, but then you need to specify them in another file. Which isn't very usefull.

Well, thanks for the replies and ideas anyway

Off topic
Can you recommend any other tutorials like bkerndev?

I know how some of the bitwise operators like << and & work,
but what are &=, ^=, |= and %

[Kemp]

Most of the things that have an operator followed by equals do the operation with the argument and the original variable, for example:

a += b is the same as a = a + b

% is the modulus operator, it gets the remainder from a division, so

9 % 4 would be 1 (9 / 4 is 2 with a remainder of 1)

[Tora OS]

Can you recommend any other tutorials like bkerndev?

OSDever has some great tutorials and documentations, and since they are back now...

[Tora OS]

BTW...this is just because i like proving people wrong:


http://babb.sytes.net/PUB/Tora%20OS/toraos_bigk.JPG

Code: Select all

; This is the kernel's entry point.
[BITS 32]
global start
start:
    mov esp, _sys_stack     ; This points the stack to our new stack area
    jmp stublet ; Jump over the GRUB info crap

; This part MUST be 4byte aligned, so we solve that issue using 'ALIGN 4'
ALIGN 4
mboot:
    ; Multiboot macros to make a few lines later more readable
    MULTIBOOT_PAGE_ALIGN   equ 1<<0
    MULTIBOOT_MEMORY_INFO   equ 1<<1
    MULTIBOOT_AOUT_KLUDGE   equ 1<<16
    MULTIBOOT_HEADER_MAGIC   equ 0x1BADB002
    MULTIBOOT_HEADER_FLAGS   equ MULTIBOOT_PAGE_ALIGN | MULTIBOOT_MEMORY_INFO | MULTIBOOT_AOUT_KLUDGE
    MULTIBOOT_CHECKSUM   equ -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)
    EXTERN code, bss, end

    ; This is the GRUB Multiboot header. A boot signature
    dd MULTIBOOT_HEADER_MAGIC
    dd MULTIBOOT_HEADER_FLAGS
    dd MULTIBOOT_CHECKSUM
    
    ; AOUT kludge - must be physical addresses. Make a note of these:
    ; The linker script fills in the data for these ones!
    dd mboot
    dd code
    dd bss
    dd end
    dd start

; This is where all the action happens
stublet:
    extern _main ; Declare that MAIN is in the C File.
    call _main   ; Call MAIN (hello? how are you? Im doing pretty good myself. Well, goodbye.)
    jmp $      ; MAIN finished. Dont know how though. 

Look fimilar? except for some changed comments?

[Martius]

Thanks for the reply

jmp $ ; MAIN finished. Dont know how though.
main can finish in case you forget the infinite loop in it

and thanks for your proof that I'm wrong

but can you try one thing more for me, use a much larger string
by including this file http://home.wanadoo.nl/frank.silvis/verylongstr.h
cause this is what stresses my GRUB

Maybe I'm just nuts. Maybe 20kb's of code will work, but many kb's of text won't. Who'll tell ...