Siemens SIMATIC Rack PC 547B, Operating Instructions Manual

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Detailed descriptions
15.3 Interrupt assignments
SIMATIC Rack PC 547B
106
Operating Instructions, 12/2007, A5E01127519-02
Exclusive PCI hardware interrupt
Applications demanding high-performance interrupt handling require a 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)
Exclusive interrupts are not available when the device is shipped. An exclusive interrupt can
only be used and set for the PCI slots 1 and 2. This requires that the USB 1.1 channels are
disabled in the BIOS setup: Advanced > USB Enable Ports > none
Further exclusive interrupts for use at the slots are not available.
Assigning an exclusive interrupt 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.
Depending on the system configuration, it is possible that the same interrupt is assigned to
several slots. This functionality is known as interrupt sharing. There is no exclusive interrupt
available in PIC mode. Disable specific system resources in order to obtain exclusive
interrupts. The resulting free interrupt can assigned to a PCI slot in the BIOS setup. To do
this, change the slot setting from "Auto" to a free interrupt number:
Advanced > PCI Configuration > PCI IRQ Line 1 to 8 > select an interrupt (possible
interrupts are IRQ 3-7, 9-12, 14-15).
Example:
You require an exclusive IRQ for slot 4 and serial port 2 is not used.
1.
Disable serial port 2, so that IRQ3 becomes free
Advanced > PCI Configuration > Serial 2: disabled
2. Assign IRQ 3 to slot 4
Advanced > PCI Configuration > IRQ 3