Datasheet

3−16
Table 3−9. Interrupt Mask and Flag Registers
CARD TYPE EVENT MASK FLAG
16-bit memory
Battery conditions (BVD1, BVD2) ExCA offset 05h/45h/805h bits 1 and 0 ExCA offset 04h/44h/804h bits 1 and 0
16-bit memory
Wait states (READY) ExCA offset 05h/45h/805h bit 2 ExCA offset 04h/44h/804h bit 2
16-bit I/O
Change in card status (STSCHG) ExCA offset 05h/45h/805h bit 0 ExCA offset 04h/44h/804h bit 0
16-bit I/O
Interrupt request (IREQ) Always enabled PCI configuration offset 91h bit 0
All 16-bit PC
Cards
Power cycle complete ExCA offset 05h/45h/805h bit 3 ExCA offset 04h/44h/804h bit 3
Change in card status (CSTSCHG) Socket mask bit 0 Socket event bit 0
CardBus
Interrupt request (CINT) Always enabled PCI configuration offset 91h bit 0
CardBus
Power cycle complete Socket mask bit 3 Socket event bit 3
Card insertion or removal Socket mask bits 2 and 1 Socket event bits 2 and 1
Functional interrupt events are valid only for 16-bit I/O and CardBus cards; that is, the functional interrupts are not
valid for 16-bit memory cards. Furthermore, card insertion and removal-type CSC interrupts are independent of the
card type.
Table 3−10. PC Card Interrupt Events and Description
CARD TYPE EVENT TYPE SIGNAL DESCRIPTION
Battery conditions
CSC
BVD1(STSCHG)//CSTSCHG
A transition on BVD1 indicates a change in the
PC Card battery conditions.
16-bit
memory
Battery conditions
(BVD1, BVD2)
CSC
BVD2(SPKR)//CAUDIO
A transition on BVD2 indicates a change in the
PC Card battery conditions.
memory
Wait states
(READY)
CSC READY(IREQ)//CINT
A transition on READY indicates a change in the
ability of the memory PC Card to accept or provide
data.
16-bit I/O
Change in card
status (STSCHG
)
CSC BVD1(STSCHG)//CSTSCHG
The assertion of STSCHG indicates a status change
on the PC Card.
16-bit I/O
Interrupt request
(IREQ
)
Functional READY(IREQ)//CINT
The assertion of IREQ indicates an interrupt request
from the PC Card.
CardBus
Change in card
status (CSTSCHG)
CSC BVD1(STSCHG)//CSTSCHG
The assertion of CSTSCHG indicates a status
change on the PC Card.
CardBus
Interrupt request
(CINT
)
Functional READY(IREQ)//CINT
The assertion of CINT indicates an interrupt request
from the PC Card.
All PC Cards
Card insertion
or removal
CSC
CD1//CCD1,
CD2
//CCD2
A transition on either CD1//CCD1 or CD2//CCD2
indicates an insertion or removal of a 16-bit or
CardBus PC Card.
All PC Cards
Power cycle
complete
CSC N/A
An interrupt is generated when a PC Card power-up
cycle has completed.
The naming convention for PC Card signals describes the function for 16-bit memory, I/O cards, and CardBus. For
example, READY(IREQ
)//CINT includes READY for 16-bit memory cards, IREQ for 16-bit I/O cards, and CINT for
CardBus cards. The 16-bit memory card signal name is first, with the I/O card signal name second, enclosed in
parentheses. The CardBus signal name follows after a double slash (//).
The 1997 PC Card Standard describes the power-up sequence that must be followed by the PCI1520 when an
insertion event occurs and the host requests that the socket V
CC
and V
PP
be powered. Upon completion of this
power-up sequence, the PCI1520 interrupt scheme can be used to notify the host system (see Table 3−10), denoted
by the power cycle complete event. This interrupt source is considered a PCI1520 internal event, because it depends
on the completion of applying power to the socket rather than on a signal change at the PC Card interface.