ADLINK PCI-7442 - Manual (Page 79)

Register Format 67
4.4 Handling PCI Controller Registers
The PCI-7442/7443/7444 card adopts the PLX PCI-9030 PCI bus
controller. You should notice some registers when you attempt to
handle the card via low-level programming. The interrupt control
register (INTCSR; 0x4Ch) of PCI-9030 takes charge of all interrupt
information from local bus to PCI bus. When you want to develop
your own interrupt function driver, both interrupt registers in PCI-
9030 and in the PCI-7442/7443/7444 card have to work together.
For detailed information about the interrupt control register in PCI-
9030, refer to the PCI-9030 databook.
The PCI-7442/7443/7444 card’s function library provides simple
and easy-to-use functions that handle interrupt procedures. These
functions eliminate the handling of the interrupt register in the PCI
controller. It is recommended that you use these functions instead
of developing your own interrupt functions.