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From: Ralf.Brown@B.GP.CS.CMU.EDU
Newsgroups: comp.os.msdos.programmer
Subject: Re: Stack Segment...  Can I change it?
Message-ID: <26fb5350@ralf>
Date: 22 Sep 90 12:04:32 GMT
Sender: ralf@b.gp.cs.cmu.edu
Organization: Carnegie Mellon University School of Computer Science
Lines: 25
In-Reply-To: <8158@tekgvs.LABS.TEK.COM>

In article <8158@tekgvs.LABS.TEK.COM>, toma@tekgvs.LABS.TEK.COM (Tom Almy) wrote:
}In article <31074@nigel.ee.udel.edu> shearer@cis.udel.edu (Rob Shearer) writes:
}>I use TC++ version 1.0.  
}>After the main() delcaration i would like to tell the system WHERE to use
}>the stack..  
}>can I just poing _SS = FP_SEG(newlocation);
}>                 _SP = FP_OFF(newoffset);
}
}Several considerations (generic across any compiler for the 80x86):
}
}2. In the sequence you give above, you must make sure that the generated
}   instruction that loads the SP immediately follows the one that loads SS.
}   The mov ss,.. instruction automatically inhibits interrupts for one
}   following instruction.
}   If this is not the case, you will need to disable interupts while
}   changing stacks.

You will also need to disable interrupts if the code can be run on an 8088,
as early versions of that chip have a microcode bug which results in
interrupts not being disabled for the instruction after a change to SS.
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