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From: jfc@athena.mit.edu (John F Carr)
Newsgroups: comp.sys.ibm.pc.rt
Subject: Re: integer alignment problems on RT
Keywords: RT 6150 032 ROMP alignment
Message-ID: <14927@bloom-beacon.MIT.EDU>
Date: 7 Oct 89 02:46:40 GMT
References: <162@eliza.edvvie.at> <2396@ibmpa.UUCP>
Sender: daemon@bloom-beacon.MIT.EDU
Reply-To: jfc@athena.mit.edu (John F Carr)
Organization: Massachusetts Institute of Technology
Lines: 18

>If the RT was being 
>designed today I'm sure that it would have implemented an Interrupt on 
>Unaligned Access bit in the ICS register.

I found this comment in the AOS kernel sources (sys/locore.c):

	/*
	 * determine the processor model (either SGP or ROMPC) by setting
	 * the Interrupt On Unaligned Access bit which is always 0 on the SGP
	 * processor.
	 */

This is the only reference anywhere I have seen to the bit in question.
The technical reference describes this bit as "reserved -- must be 0".

Someday I'll try setting this bit to see what happens.

    --John Carr (jfc@athena.mit.edu)