Date: Sun, 24 Oct 1999 09:26:54 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: Martin Czamai <Martin_Czamai AT peak-service DOT com>
cc: djgpp AT delorie DOT com
Subject: Re: Programming Hardware Interrupts
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On Thu, 21 Oct 1999, Martin Czamai wrote:

> I'm trying to program a short test-programm for a PCI device. The PCI
> controller gives me the correct data from the sub-device, which is an other,
> external controller. The interrupt-flags are reseted correct on both
> devices, but my interrupt serivce routine (ISR) works only once per booting
> :-(((

The usual way to debug these problems is to look at the bits in the
Interrupt Request Register and the Interrupt In-Service Register of
the 8259 Interrupt Controller.  These bits will show you (1) whether
the interrupt is being requested by the PCI device, and (2) whether
your EOI command does its thing by resetting the relevant bit in the
In-Service register.