From: "Martin Peach" <martin AT loplop DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: hardware ints
Date: Sun, 15 Aug 1999 19:06:53 -0400
Organization: Communications Accessibles Montreal, Quebec Canada
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To: djgpp AT delorie DOT com
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I am trying to catch received characters from the UART at COM2 using IRQ3. I
think I have installed my (protected mode) handler the right way using the
go32 dpmi functions as described in the faq, but my handler is never called,
nor does the thing crash. I can see that I am getting overrun errors from
the received characters and I am able to receive them OK by polling.
Although I enabled the receive character interrupt in the IER register of
the UART and set the PIC interrupt mask, I am not sure if the UART is
generating interrupts to the 8259 PIC. Is there a way to check for this? Is
it OK to use a protected mode handler for the COM ports? Is something else
getting to my interrupts before I get there? Do I need to intitalize
something else to enable interrupts?
Too many questions for one day...
Martin