Detailed descriptions
16.4 System resources
SIMATIC Rack PC 847B
Operating Instructions, 06/2008, A5E02203168-01
159
PCI / PCIe cards and the on-board PCI / PCIe devices require PCI interrupt channels. These
interrupt channels can be shared and are plug-and-play compatible, that is, several devices
can share the same interrupt. The IRQ is assigned automatically.
PCI interrupt channels must be derived from the PIC interrupt pool, that is PCI modules also
use PIC resources. These IRQ channels are assigned automatically.
The Host PCI IRQ channels A to H are permanently assigned in APIC mode. These default
settings cannot be modified.
The Host PCI IRQ channels A to H in PIC mode are assigned automatically in BIOS. The
assignment can be changed by disabling functions.
16.4.2.3
Memory address assignments
PCI VGA modules can be operated with expansion ROM up to 48K.
Address
from
to
Size
Description of the basic
function
Possible alternative
function
0000 0000
0007 FFFF
512K
Conventional system memory
0008 0000
0009 F7FF
127K
Conventional system memory
extended
0009 F800
0009 FFFF
2K
XBDA, extended Bios Data
Area
000A 0000
000A FFFF
64K
VGA graphics refresh memory Shared SMM for power
management
000B 0000
000B 7FFF
32K
SW graphics / text refresh
memory
Not used
000B 8000
000B FFFF
32K
VGA graphics/text refresh
memory
000C 0000
000C BFFF
48K
VGA BIOS expansion
000C 0000
000C E9FF
59K
1)
VGA BIOS
Always occupied
000C F000
000D FFFF
68K
1)
Not used (no RAID, no PXE)
via EMM High DOS
Memory
000C F000
000C FFFF
4K
1)
PXE
000D 0000
000D FFFF
64K
1)
Not used (no RAID, with PXE) via EMM High DOS
Memory
000C F000
000D 37FF
18K
1)
RAID
000D 3800
000D FFFF
50K
1)
Not used (RAID, no PXE)
via EMM High DOS
Memory
000C F000
000D 47FF
22K
1)
RAID and PXE
000D 4800
000D FFFF
46K
1)
Not used
000E 0000
000E 1FFF
8K
USB
000E 2000
000E 3FFF
8K
DMI data
000E 4000
000F FFFF
112K
System BIOS
0010 0000
CFFF FFFF
3.2 GB
System memory 4 GB memory
configuration
Depends on memory
configuration
E000 0000
FFEF FFFF
511 MB
PCIe Configuration Space
FFF0 0000
FFFF FFFF
1 MB
Firmware HUB
1)
Optional memory allocation, depending on settings in BIOS Setup