Texas Instruments PCI7611, PCI7411, PCI7621 PC Card Functional and Card Status Change Interrupts

3.7.1PC Card Functional and Card Status Change Interrupts

PC Card functional interrupts are defined as requests from a PC Card application for interrupt service and are indicated by asserting specially-defined signals on the PC Card interface. Functional interrupts are generated by 16-bit I/O PC Cards and by CardBus PC Cards.

Card status change (CSC)-type interrupts are defined as events at the PC Card interface that are detected by the PCI7x21/PCI7x11 controller and may warrant notification of host card and socket services software for service. CSC events include both card insertion and removal from PC Card sockets, as well as transitions of certain PC Card signals.

Table 3−10 summarizes the sources of PC Card interrupts and the type of card associated with them. CSC and functional interrupt sources are dependent on the type of card inserted in the PC Card socket. The four types of cards that can be inserted into any PC Card socket are:

•16-bit memory card

•16-bit I/O card

•CardBus cards

•UltraMedia card

Table 3−10. 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
	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			ExCA offset 05h/45h/805h bit 0	ExCA offset 04h/44h/804h bit 0
			(STSCHG)
16-bit I/O/
	Interrupt request (IREQ)			Always enabled	PCI configuration offset 91h bit 0
UltraMedia
All 16-bit PC
Cards/
Smart Card	Power cycle complete			ExCA offset 05h/45h/805h bit 3	ExCA offset 04h/44h/804h bit 3
adapters/
UltraMedia/
Flash Media
	Change in card status (CSTSCHG)			Socket mask bit 0	Socket event bit 0
	Interrupt request			Always enabled	PCI configuration offset 91h bit 0
CardBus		(CINT)
	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.

3−17