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New PCI's designed to share IRQs. BUT...
like most PC hardware, there are exceptions.

Here's a good page with info on IRQ sharing on the PCI bus, with an emphasis on problems NICs can have.

[link|http://personal.bellsouth.net/sdf/h/b/hburgiss/dsl/survival/irq.htm| [link|http://personal.bellsouth.net/sdf/h/b/hburgiss/dsl/survival/irq.htm|http://personal.bel...ival/irq.htm]]

Basically, IIRC, the PCI bus is more sophisticated than the old ISA bus in that it can discrimiate between two devices raising the same interrupt signal. Edge- versus level-triggering seems to raise a flag with me. Check Google for more details...

HTH.

Cheers,
Scott.
New Good crib sheet..
Thanks. Saved.

Interesting re SBLive stealing an Irq for DOS use - about which Windoze is oblivious!

Also noted my E-machine has modem in 1st PCI slot adjacent to AGP! but - works like charm.

Good reminder too, to make sure I remembered to disable the secondary IDE and second floppy in BIOS in the new boxes.

Now as to edge VS level- triggering (??) - fer us scope types that rings a bell, but also a bit sophisticated for a toy box I'd a thunk: that is, for it to reliably discriminate / flip - for one trigger-level setting VS a slightly different criterion. At a 100 - 200 MHz bus rate, say !

(If you find that ref, be curious how they Do that.)


Thanx,

A.
New Edge versus Level triggering of interrupts...
I misrememberd. ISA uses edge, PCI uses level.

[link|http://mailman.real-time.com/pipermail/linux-kernel/2001-March/023682.html|Here's] a bit I found about it. I'm no expert on this stuff. There should be better info out there - especially on Intel's site.

HTH.

Cheers,
Scott.
New See what you mean. Heh! an analog! e- problem..
If my reading between lines is close enough:

What he's calling "edge" triggering is.. that sort of detector, commonly using a Schmitt Trigger circuit: a feedback device which enhances the risetime via.. yup pos feedback! to give a thus faster dV/dt as a trigger pulse. What he calls "level triggering" implies an intentionally 'slower" device which is not concerned with dV/dt so much as just "change state when V= x.yz V".

Guess I'll poke around a bit; hard to see how same line from an "Irq detector" under s/w control - could parse the two - but it seems that the Vectra didn't.. too well. How'd ya find That!?

(It's amazing the amount of stuff you can see with a real analog GHz scope on these boards - let alone decipher)


A.
     Presario 7110US, 17", color printer. $1499.97 Deal? - (Another Scott) - (21)
         Sounds good. -NT - (static)
         Wondering re Compaq - (Ashton) - (1)
             My mom's Presario 5000 seems pretty standard. - (Another Scott)
         Careful... - (bepatient) - (16)
             IRQs only an issue for ISA peripherals. -NT - (pwhysall) - (15)
                 Umm could you expand on that? - (Ashton) - (8)
                     Brother, can you spare an IRQ? - (orion)
                     PCI's designed to share IRQs. BUT... - (Another Scott) - (3)
                         Good crib sheet.. - (Ashton) - (2)
                             Edge versus Level triggering of interrupts... - (Another Scott) - (1)
                                 See what you mean. Heh! an analog! e- problem.. - (Ashton)
                     IRQ Sharing In Action - (pwhysall) - (2)
                         Re: IRQ Sharing is a two edged sword. - (a6l6e6x)
                         Amiga also shared IRQs - (SpiceWare)
                 B*llsh*t. - (qstephens) - (5)
                     Some devices do not work well with others - (orion) - (4)
                         Why...________________________________"almost"____?? -NT - (Ashton) - (3)
                             Why almost? - (orion) - (2)
                                 OK though not compelling for a non-techno wanting stability. -NT - (Ashton) - (1)
                                     You want stability for a non-techno? - (orion)
         Keyboard should be fine - (SpiceWare)

I've had worse!
123 ms