User`s guide

PCI Bus Considerations
You can have the drivers locate PCI devices in one of the following ways:
• If the system has one board of any one type, you can use the d riv er
slot
option to search for the first board that matches a vendor and device ID. To
initiate this search, set this option to
-1.
• If the system contains m ultiple boa rds o f the same type, setting the
slot
option to -1 does not find the additional boards. In that case, specify the
bus and slot numbers with the vendor and device IDs.
PCI Configuration Space API
Before you can access a PCI device, you need to access the configuration space
to locate the board in the target PC memory. This section describes the
proceduretodothis.
For PCI devices, the driver will n eed to access the P C I configuration space
for the board. This space contains relevant board information such as the
base address and acces s type (I/O port or memory mapped). The xPC Target
software provides functions that allow the driver to access this space.
• Vendor and device ID — The d river searches all boards for the specified
vendor (manufacturer) and device ID. The PCI Steering Committee, an
independent standards body, assigns a unique vendor ID (
uint16)toeach
PCI board vendor. Each vendor then assigns a unique ID to each PCI board
type it supports.
Note Vendor and device IDs do not always uniquely identify a board. For
example, all boards that use the PLX-9080 bus interface chip have a vendor
ID of 10B5 (the vendor ID assigned to PLX Technology , Inc.). The device
ID for the chip is 9080. In cases like this, to select a particular board that
contains this chip, you must use a subvendor and subdevice ID in a ddition
to the vendor and device IDs.
• Slot number or bus and slot number — T he driver looks only for the board
that matches the specified vendor and device ID and slot number.
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