>                         movl    %0, a1
>                         movl    %1, a3
>                         jbsr    a1@
> 
> I'm reading that as 
> 			MOVE.L	#$0, A1
> 			MOVE.L 	#$1, A3
> 			JSR	(A1)
> 
> Is that a correct interpretation? If it is, then it is jumping to address 0.

It would help to know exactly where you're seeing this code.  I think
you're looking at macrom.c in ADBAlternateInit() from your earlier
comments.  The actual code is an asm() statement in the C file.

In that context, the %0 and %1 are positional parameters.  In this case,
that's saying (in moto syntax):
	move.l	mrg_ADBAlternateInit, a1
	move.l	ADBBase, a3
	jsr	(a1)

-allen

-- 
Allen Briggs - end killing - allen.briggs@bev.net ** MacBSD == NetBSD/mac68k **
   Where does all my time go?  <a href="http://www.netbsd.org/">Guess.</a>