Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!LOVE.MIT.EDU!krowitz
From: krowitz@LOVE.MIT.EDU (David Krowitz)
Newsgroups: comp.sys.apollo
Subject: GPIO question
Message-ID: <8810211939.AA07693@love.mit.edu>
Date: 21 Oct 88 19:39:01 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 24

I'm getting occasional system crashes when I'm running
a printer for which I wrote a GPIO driver. The crash
status says:

$ stcode 120031
illegal page fault in user gpio interrupt routine (OS/fault handler)

But all of the variables I refer to in the interrupt
routine are defined (Pascal DEFINE statement) within
that module, or are pointers to variable defined
within that module. I am under the impression that
the entire interrupt library is automatically 'wired'
into physical memory when the device is aquired. Is
this correct? Is there a limit to the size of the
interrupt routine and its buffers (I'm using a
60Kb ring buffer) that I could be exceeding?


 -- David Krowitz

krowitz@richter.mit.edu   (18.83.0.109)
krowitz%richter@eddie.mit.edu
krowitz%richter@athena.mit.edu
krowitz%richter.mit.edu@mitvma.bitnet
(in order of decreasing preference)