Re: PCI riser cards and PCI irq routing, etc

[Udo van den Heuvel <udovdh@xs4all.nl>]

Krzysztof Halasa wrote:
> Udo van den Heuvel <udovdh@xs4all.nl> writes:
> 
>> I will try a different case with a different dual PCI riser card soon.
>> This Morex riser has DN20-31 or so, so more options.
>> Could this help solve my irq issue? (try 4 consecutive DNs until I have
>> the right mapping?)
> 
> I don't think so. Unless you can configure INT connections on the riser
> card, of course.
> 
> You need DN19 for the second slot (and perhaps 10 would work with
> double INTx rotation), that's fixed in the BIOS.

I have DN19 and DN20 now and it doesn't work.
Only because the INT mapping on the riser is not right?

http://www.morex.com.tw/drawing/MAR122-J%20Drawing.pdf shows some IDSEL
jumper with ADxx numbers. What could these be?
Photo at http://www.morex.com.tw/products/imgproduct/100-1.jpg.

Still DN's?

>> This Morex riser has DN20-31 or so, so more options.
>
> OTOH I wonder how do they use DN 21-31? The board uses lines AD11 to AD31
> (21 lines) for selecting devices #0 - #20. 32-bit PCI bus has only 32
> address/data lines :-)
>
> Perhaps they mean AD20-AD31 lines = device #9 - #0x14=20? If that is
> the case, you can try:
> - their "DN30" = device 0x13 = 19, which is apparently what the VIA riser
>   card does,
> - their "DN21" = device 0xA = 10, which could work as well.
>
> I'm afraid both would require (different) soldering.

So at least try the different jumper settings (without additional info,
I hope Morex responds to my emails).
Else do a little soldering.

> It's possible that the riser card includes a bridge, though. A bridge
> chip can select devices differently and thus it can handle 32 devices.

Looking at the photo I don't think I see a bridge...