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Article #6547_Debugger trap failure
From: Brian H. Powell
Date: Thu, 24 Jul 1986 22:55
Date: Thu, 24 Jul 1986 22:55
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I was just reading the MacsBug version 5.1 documentation that came
in Supplement Volume I, Issue 3 (the March/June 1986 supplement). I noticed
on one of the pages that they don't want anyone using Line-1111 traps anymore
to break into a debugger. (They will interfere with the 68881.) (And by the
way, this warning was in the December/February supplement also, but I didn't
notice it then.)
Fine, I thought. I am always ready to follow the Apple Guidelines. I'll
just change this "dc.w $ff00" statement to the approved "_Debugger" trap.
Assemble; link. Run.
Boom. A bomb box (with a debugger installed!) ID=12. The old dsCoreErr.
Unimplemented trap. My debugger was virtually helpless. Reboot.
You see, Apple doesn't really have an $a9ff (_debugger) trap. They fake
it in the debugger. I think it only works with the new 5.* series MacsBugs.
I was using a Mac+ with MacNub A debugged by a 128K Mac running MacDB A. I'm
using a (Darin Adler) NoQuiche system, version 3.2.
Conclusion:
The documentation is misleading. Just thought you'd want to know.
Since
1) I don't plan to have the debug trap in the final code, and
2) I don't have a 68881 yet,
this isn't really a problem. I'd much rather use MacDB than MacsBug since
I have two macs, so I'll continue using the Line-1111 traps to debug. I just
think Apple should have qualified the warning.
Brian H. Powell
UUCP: {ihnp4,seismo,ctvax}!ut-sally!brian
ARPA: brian@sally.UTEXAS.EDU
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Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!mnetor!seismo!ut-sally!brian From: brian@ut-sally.UUCP (Brian H. Powell) Newsgroups: net.micro.mac Subject: _Debugger trap failure Message-ID: <5401@ut-sally.UUCP> Date: Thu, 24-Jul-86 18:55:26 EDT Article-I.D.: ut-sally.5401 Posted: Thu Jul 24 18:55:26 1986 Date-Received: Thu, 24-Jul-86 21:51:43 EDT Organization: U. Texas CS Dept., Austin, Texas Lines: 29 Keywords: MacDB, What Apple meant to say was...