The ImageSig

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The ImageSig

Postby MichaelSammels » Sun Mar 06, 2011 2:48 pm

In the Stage2.asm file, the "ImageSig db 'PE'" is present. Is it possible to change this signature so I can use this bootloader with a kernel written also in ASM? Or do I need to create an EXE/C based kernel with this bootloader?
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Re: The ImageSig

Postby Mike » Mon Mar 07, 2011 4:02 pm

Hello,

The signature is specific to PE executables. If you would like to use a PE executable written in assembly language or C the signature must match. If you want to use a custom image format or a non-PE image then it is indeed not required.

The boot loader was designed to parse PE executables so you will need to modify it slightly in order to parse non-PE images. Alternative bootloaders that support MultiBoot can also provide a solution.
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Re: The ImageSig

Postby MichaelSammels » Mon Mar 14, 2011 1:06 am

Hello Mike, thank you for your response. Would you be able to provide me with an example of a bootloader (not GRUB, LILO or other such ones, more custom like yours), or a modification of your own bootloader which would load flat-binaries?
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Re: The ImageSig

Postby Mike » Mon Mar 14, 2011 5:06 am

Hello,

Our in-house bootloader can load and execute flat binaries that are multiboot compliant. An example from the bootloader will not help however.

What I personally recommend is to try it yourself first: Decide on a standard to use and the goals for the bootloader and kernel relationship, if any. Then implement the standard. The standard can be complex or as simple as the bootloader checking for a specific magic number at offset 3 in the kernel.

If you still request an example, please let me know if you would like it as a modification of the series bootloader or our routine in our in-house loader (in C).
Lead Programmer for BrokenThorn Entertainment, Co.
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Email: webmaster@brokenthorn.com
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Re: The ImageSig

Postby MichaelSammels » Wed Mar 16, 2011 12:50 pm

Hello,

Please see the Personal Message which I have sent to you.

Michael
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