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From: jjr@sgtech.UUCP (John Radigan)
Newsgroups: comp.os.os2.programmer
Subject: Re: Sharing Interrupts on a PS/2
Message-ID: <87@sgtech.UUCP>
Date: 4 Jun 91 14:08:35 GMT
Article-I.D.: sgtech.87
References: <1991May31.194019.3122@dialogic.com>
Sender: news@sgtech.UUCP
Lines: 21

From article <1991May31.194019.3122@dialogic.com>, by gerry@dialogic.com (Gerry Lachac):
> 	Driver A calls  SetIRQ(3,ISRa) and later,
> 	Driver B calls  SetIRQ(3,ISRb)
> 
> 
> When an interrupt 3 comes in, does OS/2 call Driver A's ISR first
> (since it was the first set) or Driver B's?

I quote from IBM OS/2 Programming Tools and Information 1.2, I/O Subsystems and
Device Support, Volume 1, page 2-20. 

   "POSITION RULE An interrupt handler that shares an interrupt level must
         not depend on its position in the list of handlers for that inter-
         rupt level."

There is no mention of the calling sequence applied by the interrupt manager.


--
John Radigan, Star Gate Technologies, Inc., Solon, Ohio  
Email: jjr@sgtech.uucp		Telephone: (216) 349-1860 x666