Chapter 4: Address Selection
The PCI architecture is Plug-and-Play. This means the BIOS or Operating System determines the
resources assigned to PCI cards, rather than the user selecting these resources with switches or
jumpers. As a result, the card’s base address cannot be changed, it can only be determined. It’s
possible to use the Windows95/98/NT device manager to specify system resources but that method is
beyond the scope of this manual.
To determine the base address that has been assigned to the card, run the provided PCIFind.EXE
utility program. This utility will display a list of all of the cards detected on the PCI bus, the addresses
assigned to each function on each of the cards, and the respective IRQs and DMAs (if any) allotted.
Alternately, some operating systems (Windows 95/98/2000) can be queried to determine which
resources were assigned. In these operating systems, you can use either PCIFind or the Device
Manager utility from the System Properties Applet of the control panel. These cards are installed in the
Data Acquisition class of the Device Manager list. Selecting the card then clicking
Properties
, then
selecting the Resources Tab will display a list of the resources allocated to the card.
The PCI bus supports a minimum of 64K of I/O space, your card’s address may be located anywhere in
the 0400 to FFF8 hex range. PCIFind uses the Vendor ID and the Device ID to search for your card
then reads the base address and IRQ assigned. If you want to determine the base address and IRQ
assigned, use the following information:
The Vendor ID code for the card is 494F (ASCII for “IO”).
The Device ID code for the card is 10C9.
Manual PCI-COM-1S
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