Specifications

106 ST-133/ST-133A Controller Manual Version 2.H
Slot Type Status I/O Address(s) Interrupt
1 (ISA) ISA Network Card 200-210 11
2 (PCI) PCI Video Card FF00-FFFF 15
3 (ISA) ISA Sound Card 300-304 9
4 (PCI) Empty N/A N/A
Table 9. I/O Address & Interrupt Assignments
Before Installing Serial Card
As shown, there are no conflicts, allowing the three peripheral cards to operate properly.
If the PCI Serial card were then installed, the BIOS would interrogate the PCI cards and
may reassign them new address and interrupt values as follows.
Slot Type Status I/O Address(s) Interrupt
1 (ISA) ISA Network Card 200-210 11
2 (PCI) PCI Video Card FE00-FEFF 11
3 (ISA) ISA Sound Card 300-304 9
4 (PCI) Princeton Instruments PCI
Serial Card
FF80-FFFF 15
Table 10. I/O Address & Interrupt Assignments
After Installing Serial Card
As indicated, there is now an interrupt conflict between the ISA Network Card and the
PCI Video card (both cards have been assigned Interrupt 11), causing the computer to no
longer function normally. This doesn't mean that the PCI Serial card is defective because
the computer stops functioning properly when the Serial card is installed. What it does
mean is that there is an interrupt conflict that can be resolved by changing the interrupt
level on the conflicting Network card in this example. It is up to the user to consult the
documentation for any ISA cards to determine how to make the necessary change.
Note: Changing the order of the PCI cards, that is, plugging them into different slots,
could change the address and interrupt assignments and possibly resolve the conflict.
However, this would be a trial and error process with no guarantee of success.
Diagnostics Software
Many diagnostics programs, both shareware and commercial, are available to help
resolve conflicts. Most often, all that's required is a program that will read and report the
address and interrupt assignments for each PCI device in the computer. One such
program available from Roper Scientific's Technical Support department is called
PCICHECK. When the program is run, it reports the address and interrupt assignments
for the first PCI device it finds. Each time the spacebar is pressed, it moves on to the next
one and reports the address and interrupt assignments for that one as well. In a few
moments this information can be obtained for every PCI device in the computer. Note
that, even though there are generally only three PCI slots, the number of PCI devices
reported may be larger because some PCI devices may be built onto the motherboard. A
good strategy for using the program would be to run it before installing the PCI Serial
card. Then run it again after installing the card and note any address or interrupt
assignments that may have changed. This will allow you to easily focus on the ones that