Detailed descriptions
16.2 Bus board
SIMATIC Rack PC 847B
148
Operating Instructions, 06/2008, A5E02203168-01
16.2.2
Exclusive PCI hardware interrupt
Applications demanding high-performance interrupt handling require high-speed hardware
interrupt reaction. The PCI hardware interrupt should only be used by one resource in order
to ensure high-speed reaction of the hardware.
Setting up an exclusive interrupt on the device (only APIC mode)
An exclusive interrupt can only be set and used for PCI slot 5 or 8 and 6 or 9. Further
exclusive interrupts for use at the slots are not available.
Assigning exclusive interrupts in BIOS Setup (PIC mode only)
The interrupts are automatically assigned to the slots at system startup due to the default
settings in system BIOS.
Several slots may share the same interrupt, depending on the system configuration. This
functionality is known as interrupt sharing. Exclusive interrupts are not available in PIC
mode. Disable specific system resources in order to obtain exclusive interrupts. BIOS
assigns the PIC interrupts at random during restart of the system.