From:	"Martin Peach" <martin AT loplop DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	COM port interrupts don't happen?
Date:	Tue, 17 Aug 1999 19:15:42 -0400
Organization:	Communications Accessibles Montreal, Quebec Canada
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To:	djgpp AT delorie DOT com
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I'm trying to process received characters from COM1. I have set up the UART
and can receive OK by polling the device. I have set up a protected-mode
interrupt routine which works fine if I assign INT0 (timer) interrupt to it.
When I assign IRQ4 (INT0x0C, COM1) to it, nothing happens.
The interrupt identification register says there is an interrupt pending
when I poll it, the PIC mask has the corresponding bit cleared, the CPU ints
are enabled using enable(), but my service routine is never called.
Is this normal? I've tried this on a 486 and a pentium machine with
identical results.
What am I missing here?

\/\/\/*= Martin

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