I am about to install an ISA card, and need to know what ISA addresses
and IRQs are available. My machine has both PCI and ISA slots, and some
ISA devices implemented on the processor board. Is there some sure way
of doing this? I’ve looked at several options:
I’ve looked at the enum-devices command, and can’t figure out for sure
from it’s output what ISA bus addresses are for currently installed
devices.
I could look at the ROM BIOS output as the machine boots, but i’m not
sure if that is complete. I could assume it is complete, and any
resources not used are available.
I can’t say I see in the enum configuration files where addresses are
mentioned.
–
John H. Zouck
The Johns Hopkins University
Applied Physics Laboratory
Previously, John H. Zouck wrote in qdn.public.qnxrtp.newuser:
I am about to install an ISA card, and need to know what ISA addresses
and IRQs are available. My machine has both PCI and ISA slots, and some
ISA devices implemented on the processor board. Is there some sure way
of doing this? I’ve looked at several options:
I’ve looked at the enum-devices command, and can’t figure out for sure
from it’s output what ISA bus addresses are for currently installed
devices.
I could look at the ROM BIOS output as the machine boots, but i’m not
sure if that is complete. I could assume it is complete, and any
resources not used are available.
I can’t say I see in the enum configuration files where addresses are
mentioned.
The answer is the other way around. The IRQ and memory assigned to
the ISA card have to be reserved in the CMOS setup of the computer.
You choose the IRQ you want to use for your ISA card, and set that to
be “Legacy” or “ISA” or whatever your CMOS setup calls it. Then you
choose the memory address for your ISA card and look for a “Memory
Hole” or “Reserve Memory for ISA” or some such setting in the CMOS and
make it match. When your computer boots, the IRQ and memory you
reserved for the ISA card will not be available for assignment to the
PCI cards. PCI cards fall where they may - you don’t typically
control that. The IRQ and memory addresses for PCI cards need not be
the same from one boot to the next. When you start the driver for
your ISA card, you usually have to explicitly tell the driver the IRQ
and memory address (and port number), though some drivers will attempt
to auto-detect cards.
Cheers,
Andrew