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SubjectRe: IRQ 255?
Does anyone know what the advantages/disadvantages of having an irq for a video
card are?

Pawel S. Veselov wrote:

> Hello, Bernhard!
>
> On Tue, 27 Jan 1998, Bernhard Rosenkraenzer wrote:
>
> >> Bus 0, device 2, function 0:
> >> VGA compatible controller: Cirrus Logic GD 7548 (rev 0).
> >> Fast devsel. IRQ 255.
> >>
> >> Note that the video device is on IRQ 255. Is this possibly a bug somewhere?
> >
> >IRQ 255 doesn't exist, but it looks like a (unsigned char) -1.
> >My guess is that your VGA card doesn't use an IRQ, and IRQ 255 is the PCI
> >driver's way to display this.
>
> PCI controller sets -1 ( 255 ) IRQ in two cases :
> a) The PCI device doesn't need an IRQ.
> b) There is no available IRQ to assign to this device.
>
> Bye.
> --
> Natural laws have no pity.
>
> --
> With best of best regards, Pawel S. Veselov (aka Black Angel)
> internet : vps@unicorn.niimm.spb.su ( mail,finger,talk )
> Web page : http://www.niimm.spb.su/~vps/
> ICQ : 5252265




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