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From: wkt@tuhs.org (Warren Toomey)
Subject: [TUHS] Query on PDP-11 assembly
Date: Wed, 30 Apr 2008 21:56:51 +1000	[thread overview]
Message-ID: <20080430115651.GA86539@minnie.tuhs.org> (raw)

All, I'm trying to write a PDP-11 disassembler for a.out files. I'm having
trouble dealing with jsrs. Take, for example, the code here:
http://minnie.tuhs.org/UnixTree/1972_stuff/s1/frag19.html

I can happily deal with the   jsr pc,do   type of jsr, but the ones
involving r5 have me stumped, e.g.:

	jsr	r5,questf; < nonexistent\n\0>; .even

It appears that data is being inserted into the executable directly
after the jsr instruction. How does the rts which returns from the jsr
know how much data to skip, and what is the involvement of r5 here?

Thanks,
	Warren



             reply	other threads:[~2008-04-30 11:56 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-04-30 11:56 Warren Toomey [this message]
2008-04-30 13:55 ` Brantley Coile
2008-04-30 14:41   ` Naoki Hamada
2008-05-01 23:47     ` Warren Toomey
2008-04-30 16:53   ` Milo Velimirovic
2008-04-30 17:00     ` Larry McVoy
2008-04-30 17:47       ` John Cowan
2008-04-30 17:59         ` Larry McVoy
2008-04-30 15:08 ` Carl Lowenstein
2008-04-30 16:20 James A. Markevitch

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