delorie.com/archives/browse.cgi   search  
Mail Archives: djgpp/2002/10/07/14:27:27

Message-ID: <BDD73AE8AEE3EF438E07420C2600E9F65C918A@qtiexch0.qgraph.com>
From: "Sisco, Michael" <mdsisco AT qtiworld DOT com>
To: "'djgpp AT delorie DOT com'" <djgpp AT delorie DOT com>
Subject: Int 0x22??? (DJGPP and CWSDPMI)
Date: Mon, 7 Oct 2002 13:26:51 -0500
MIME-Version: 1.0
X-Mailer: Internet Mail Service (5.5.2656.59)
Reply-To: djgpp AT delorie DOT com

We are currently performing a "stress test" on the serial comm link 
used as part of our application. The test is very simple. We send a
"poll" command to the piece of equipment with which we are communicating.
The equipment responds with a "poll response" message. The incoming
message generates a series of interrupts to tell us that there is data
available in the UART. We read and display this data before sending out
the next poll command.

This all works very well for a while. After somewhere between 0 and 15
minutes, the program will crash with the following error (example):

Int 0x22 at eip 31ee0; flags=1234
 eax=00000030 ebx=00000000 ecx=0000000c edx=00000000
 esi=0001a44a edi=00000000 ebp=00000000 esp=00002672
 cs=18 ds=38 es=af fs=0 gs=0 ss=20 error=0000

I don't understand this error indication. Int 0x22 isn't really an 
interrupt vector at all. It simply specifies the return address
to be used when an application terminates. I'm not certain how our
application could have generated this interrupt. Also, the format 
of the error display leads me to believe that this report might be
coming from CWSDPMI (see FAQ section 12.2).

If we run this test several times, we get the same result, but at
different eip values. I have traced all of these eip values and find 
them to be valid points within the test loop that we are running. The 
fact that the error is happening at different points in our loop leads 
me to believe that our problem has something to do with our interrupt 
handler, but I can't put my finger on it.

Has anyone had any experience with such an error? What can cause an int
0x22?

Thanks,

Michael

Michael D. Sisco
Software Engineer
QTI - Integration Team
<mailto:Michael DOT Sisco AT qtiworld DOT com>
(414) 566-7894

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019