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From: "Gerrit van Niekerk" <gerritvn AT gpvno DOT co DOT za>
Organization: GPvNO
To: djgpp AT delorie DOT com
Date: Mon, 21 Jan 2008 22:13:10 +0200
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Subject: RM/PM ISR
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Reply-To: djgpp AT delorie DOT com

Looking at the GDB serial port driver SER-GO32.C, I notice that the RM ISR is implemented as a 
_go32_dpmi_allocate_real_mode_callback_iret to the PM ISR.

My question: Is there really an advantage in implementing a RM ISR this way? An interrupt in RM 
will result in a switch to PM which would have happened anyway if there was no RM ISR and the 
interrupt got reflected to PM. Anything I'm missing?