Siemens SIMATIC Rack PC 840 V2 Operating Instructions Manual page 118

Detailed descriptions
16.4 System resources
PCI Interrupt Lines
Channel 1
Channel 2
Channel 3
Channel 4
PCI boards and the on-board PCI devices require PCI interrupt channels. These interrupt
1)
channels are sharable and plug and play compatible. This means several devices can share
the same interrupt. The IRQ is assigned automatically. PCI interrupt channels must be
derived from the ISA interrupt pool, which means that the PCI modules also use ISA
resources. This allocation is done automatically, too. Plug and play incompatible ISA cards
can be allocated to a free IRQ by setting the "IRQ Resource Exclusion" of the corresponding
interrupt to reserved in the BIOS Setup menu. Refer to the respective ISA module
documentation for the respective interrupt to be allocated.
These functions can be disabled in the Setup This releases allocated resources.
2)
16-20
Description
USB 1.1 controller A
Ethernet
USB 1.1 controller B
USB 1.1 controller C
VGA
USB 2.0 controllers A, B, C
PROFIBUS
Comment
fixed
2)
2)
2)
fixed
2)
free in version without PROFIBUS
2)
Operating Instructions, Edition 05/2006, A5E00248055-04
SIMATIC Rack PC 840 V2