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Full Version: Changing Active Irq In /proc/isapnp
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I'm trying to change the I/O and IRQ settings for my isa nic. It looks like its getting assigned IRQ 10 at boot:
isapnp: Scanning for PnP cards...
isapnp: Card 'SMC EtherEZ (8416)'
isapnp: 1 Plug & Play card detected total
smc-ultra.c: Presently autoprobing (not recommended) for a single card.
smc-ultra.c: ISAPnP reports SMC EtherEZ (8416) at i/o 0x240, irq 10.
smc-ultra.c:v2.02 2/3/98 Donald Becker (
eth0: SMC EtherEZ at 0x240, 00 E0 29 16 9F E2,assigned  IRQ 10 programmed-I/O mode.

Here's what my /proc/isapnp file currently looks like:

[root@localhost root]# cat /proc/isapnp
Card 1 'SMC8416:SMC EtherEZ (8416)' PnP version 1.0 Product version 1.0
 Logical device 0 'SMC8416:Unknown'
   Supported registers 0x2
   Device is active
   Active port 0x240
   Active IRQ 10 [0x2]
   Active DMA 0,0
   Resources 0
     Priority preferred
     Port 0x240-0x3e0, align 0x1f, size 0x20, 10-bit address decoding
     IRQ 3,5,7,2/9,10,11 High-Edge

I've tried adding options smc-ultra irq=3 to the /etc/modules.conf file, and then rebooting, doing an ifdown eth0 and ifup eth0 but no matter what I do it always says Active IRQ 10 in /proc/isapnp. If I try changing the device IRQ through the redhat networking option, it just adds like options line to modules.conf like I had it, but the active irq is still listed as 10. I've also tried unchecking the 'activate at boot' option, and then doing a /etc/init.d/network restart but it still shows the same thing. I'm trying to make the device use IRQ 3 and Input/Output range 0240 - 025F. Any suggestions as to how I could go about doing this?

I don't think you can change the IRQ that is assigned to the Card via linux ... that is done by the OS at bootup. You will need to use either jumpers on the card... a software program from the manufacturer to make the card boot with a different IRQ... or remove the IRQ 10 from PNP assignement in the bios to have a different IRQ assigned to the card.

The switches you are using on the driver just override the default settings if the card is assigned (by jumper or BIOS) to a different IRQ than is detected by the driver ... it doesn't affect what IRQ the OS assigns to the card.
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