IBM 86626RY Hardware Maintenance Manual - Page 41

Configuring ISA and PCI adapters You cannot assign an ISA adapter to the same interrupt that you have assigned to a PCI adapter. This is because the Netfinity 5500 M20 does not support interrupt sharing among PCI and ISA adapters. If a situation occurs where you need an additional interrupt, you can use an interrupt from another function that you might not need, such as COM2 (Interrupt 3). To configure ISA adapters, select Plug and Play and follow the instructions on the screen. See "Plug and Play" on page 31 and "Plug and Play technology" on page 164 for additional information. PCI devices automatically communicate with the server configuration information. This usually results in automatic configuration of a PCI device. If a conflict does occur, see "Resolving configuration conflicts." Multiple-function PCI adapters use more than one interrupt. When you install one of these adapters, review the IRQ assignments in the Configuration/Setup Utility programs (see "PCI routing" on page 23). Verify that the IRQ assignments are correct. The Netfinity 5500 M20 uses a rotational interrupt technique to configure PCI adapters. This technique enables you to install a variety of PCI adapters that currently do not support sharing of PCI interrupts. Resolving configuration conflicts The resources used by the server consist of IRQs, DMA, I/O ports addresses, and memory. This information is useful when a resource configuration conflict occurs. Conflicts in the configuration occur if: A device is installed that requires the same resource as another device. (For example, a conflict occurs when two adapters try to write to the same address space.) A device resource is changed (for example, changing jumper settings). A device function is changed (for example, assigning COM1 to two serial ports). A software program is installed that requires the same resource as a hardware device. The steps required to resolve a configuration error are determined by the number and variety of hardware devices and software programs that you install. If a hardware configuration error is detected, a configuration error message appears after the server completes POST and before the operating system is loaded. You can bypass the error by pressing Esc while the error message is displayed. Netfinity 5500 M20 - Type 8662 33