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From: chymes@fribourg.csmil.umich.edu (Charles Hymes)
Newsgroups: comp.sys.amiga.tech
Subject: What's the details of the Boot Proceedure?
Summary: What in the registers, and where do the two sectors get loaded?
Keywords: BootBlock, exec, floppy, disassemble
Message-ID: <1990Jul28.175504.8763@csmil.umich.edu>
Date: 28 Jul 90 17:55:04 GMT
Sender: news@csmil.umich.edu
Organization: Cognitive Science and Machine Intelligence Laboratory
Lines: 42

Its a shame that I have to do this, but because this COULD be
sensitive info:
I hearby swear that I am a responcible, honest person, and that I will
not do anthing illeagal, immoral, or malicious with any information
that is given to me on this subject.

There, with that out of the way,

I am trying to figure out what is going on with the boot code of
several programs, including the standard AmigaDos bootblock.
I need to know:

 (A) Exactly what byte does the code start running at? The RKM 1.3 says
	"location 12" but is that in decimal or Hex? Some code seems to
	alreald have run some stuff before the code at 12, decimal starts.
	Also, what is in that word after the bootblock checksum?

 (B) What do the 68k registers contain when the boot block code is loaded
	and run? Especially the Address registers, Particulary A6.

 (C) Where is the bootblock loaded into? The RKM 1.3 manual says that
	it is arbitrary, but two of the first lines in the boot code on
	one autobooting disk are:
		PHA $10?? ( I dont remember these two addresses)
		PHA $2???
	It seems that this code is relying on finding something in
	memory already in those locations. What could they be? Is this area of
	memory written into by the load boot block procedure?

Thanks for your much needed help.

Please email me here, 


Charlweed Hymerfan (A Major Dude)

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