Extracting files from a kickstart rom

[Doobrey]

seer wrote:
 the links inside the ROM are pointing to a certain "adress", so if you put the code at another adress it won't work anymore.

Yup

But then, if you know the correct location, and the intention is to "recreate" the ROM or in this case a merged 1.4 + 3.1 ROM couldn't you dump the files in RAM or disk, then "disasemble" it, and reprogram it a bit or put it back in another ROM and have the correct adresses again ?

Almost..
It depends what you`re putting into the other ROM.
If the replacement code is smaller, then it`s not a problem as you can simply overwrite the old code.
But if the new code is larger, then you`ve got to reorganise the other parts in the rom, to get the new code to fit.
 This is where it gets messy, since that means working out bucketloads of new addresses to be patched.

 But as Piru said, it`s not a trivial task to split up a ROM.You gotta know where one part ends and another starts, which isn`t always obvious  :pissed:
 Some parts are easy, as they only have 6 relocs to find, but graphics.library is a real headache , somewhere around 2500 relocs to sort out... and they vary from rom to rom.

 It ain`t an easy task, it took me over 3 months to get a working 3.9 boot rom, but it`s a lot of fun and a great way to learn more about how the AmigaOS really works.. anyway stay tuned, I`m almost ready for some suckers...erm, beta testers   :evilgrin:

[Doobrey]

AF-Domains.net wrote:
I am creating a merged 1.4 and 3.1 rom to add some of the features that were in 1.4 but were never implemented into later versions of the kickstart

What features in the 1.4 rom ??

 and also to see if I can improve any part of both of the roms.

Dunno if you can call it an improvement but I`ve been averaging around 2% space saving per resident, and that`s only doing simple optimisations.
 I`ve also managed things like removing the non-FPU code from the maths libs, saving 2kb.

[Doobrey]

 IRA isn`t too bad at dissassembly, it does miss a few instructions that are on 020+ CPUS though, leaving them as dc.w $xxxx etc.
 vda68k can catch the ones that IRA can`t do

 For reassembly, give phxass a whirl.

[Doobrey]

Hang on till tomorrow..I should have something to make life a lot easier  :sealed:

Be warned, it`s docs are crap..I`m not a {bleep}ing novelist  :-)

[Doobrey]

Piru wrote:
Just like real 1.x Kickstart ROM.

Looking at Piru`s avatar,  he doesn`t look old enough to remember Kickstart 1.x  :-D

[Doobrey]

 Well, I hope this is of use to someone.
 It only handles Kickstart 40.68 (both A1200 and A4000D), and 40.63 for the A500/600/2000, and the AmigaOSRomupdate files.

 Any probs,gimme a yell.

*edit*
 New version with a couple of tools thrown in for free.
RomSplit 0.8