User`s guide

Registers
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3
Registers
The descriptions of the registers and structure of the PCI-6308 Series are
outlined in this chapter. The information in this chapter will assist
programmers, who wish to handle the card with low-level programs.
In addition, the low level programming syntax is introduced. This information
can help beginners to operate the 743X in the shortest possible time.
3.1 PCI PnP Registers
This PCI card functions as a 32-bit PCI target device to any master on the
PCI bus. There are three types of registers: PCI Configuration Registers
(PCR), Local Configuration Registers (LCR) and PCI-6308 registers.
The PCR, which is PCI-bus specifications compliant, is initialized and
controlled by the plug & play (PnP) PCI BIOS. Users may obtain more
information on the PCI BIOS specification to better understand the operation
of the PCR. Please contact PCISIG to acquire the specifications of the PCI
interface.
The PCI bus controller PCI-9050 is provided by PLX technology Inc.
(www.plxtech.com). For more information about the LCR, please visit PLX
technology’s web site to download relative information. It is not necessary for
users to fully understand the details of the LCR if the software library
provided is used. The PCI PnP BIOS assigns the base address of the LCR.
The assigned address is located at an offset of 14h from the PCR.
The PCI-6308 registers are discussed in the next section. The base address,
which is also assigned by the PCI PnP BIOS, is located at an offset of 18h
from the PCR. Therefore, users can read the address 18h from the PCR to
obtain its base address by using the BIOS function call. Do not attempt to
modify the base address and interrupt that have been assigned by the PCI
PnP BIOS, it may cause resource conflicts with your system.