[comp.sys.apollo] forwarded message

vasta_j@apollo.UUCP (Jane K. Vasta) (11/01/88)

Date: Fri, 21 Oct 88 15:39:01 EDT 
From: love.MIT.EDU!krowitz@umix.UUCP (David Krowitz)
To: apollo@umix.UUCP
Subject: GPIO question

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
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