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Old 24 January 2006, 06:29   #9
Joe Maroni
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Execbase is always $4
LVO for Superstate is -150

first you move the execbase into A6 (library bases must ever be in A6 if you call any functions of them !)
then you jump to subroutine "Superstate"
this function returns the old user stack (supervisor has its own stack !) in D0
to save it for later use you put it with a move to variable "savesp"

that´s how i would understand it...

more details:

it is allowed to change from supervisor mode into user mode but not in the other direction...
the function "superstate" just causes an exception and then jumps to the routine that starts at $020 (vector $08)

BTW: first post edited..

Last edited by Joe Maroni; 24 January 2006 at 07:38.
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