PCI1210GGU Datasheet, PDF (38/128 Pages) Texas Instruments – PCI1210 GGU/PGE PC CARD CONTROLLERS

PCI1210 GGU/PGE
PC CARD CONTROLLERS
SCPS032A– APRIL 1998
SMI support in the PCI1210 (continued)
Table 14. SMI Control
BIT NAME
SMIROUTE
SMISTAT
SMIENB
FUNCTION
SMI route. This shared bit controls whether the SMI interrupts are sent as a CSC interrupt or as IRQ2.
SMI status. This bit is set when an SMI interrupt is pending. This status flag is cleared by writing back a 1.
SMI interrupt mode enable. When set, SMI interrupt generation is enabled.
If CSC SMI interrupts are selected, then the SMI interrupt is sent as the CSC. The CSC interrupt can be either
level or edge mode depending upon the CSCMODE bit in the ExCA global control register.
If IRQ2 is selected by SMIROUTE, the IRQSER signaling protocol supports SMI signaling in the IRQ2 IRQ/Data
slot. In a parallel ISA IRQ system, the support for an active low IRQ2 is provided only if IRQ2 is routed to either
MFUNC1, MFUNC3 or MFUNC6 through the multifunction routing register.
power management overview
TI has expended great effort to provide a high-performance device with low power consumption. In addition to
the low-power CMOS technology process used for the PCI1210, various features are designed into the device
to allow implementation of popular power-saving techniques. These features and techniques are discussed in
this section.
CLKRUN protocol
The PCI CLKRUN feature is the primary method of power management on the PCI interface of the PCI1210.
CLKRUN signalling is provided through the MFUNC6 terminal. Since some chipsets do not implement
CLKRUN, alternate power savings features are provided. For details on the CLKRUN protocol refer to the PCI
Mobile Design Guide.
The PCI1210 does not permit the central resource to stop the PCI clock under any of the following conditions:
D The KEEPCLK bit in the system control register is set.
D The PC Card-16 resource manager is busy.
D The PCI1210 CardBus master state machine is busy. A cycle may be in progress on CardBus.
D The PCI1210 master is busy. There may be posted data from CardBus to PCI in the PCI1210.
D There are pending interrupts.
D The CardBus CCLK has not been stopped by the PCI1210 PCI CCLKRUN manager.
The PCI1210 restarts the PCI clock using the clockk run protocol under any of the following conditions:
D A PC Card-16 IREQ or a CardBus CINT has been asserted by either card.
D A CardBus wakeup (CSTSCHG) or PC Card-16 STSCHG/RI event occurs.
D A CardBus card attempts to start the CCLK using CCLKRUN.
D A CardBus card arbitrates for the CardBus bus using CREQ.
D A 16-bit DMA PC Card asserts DREQ.
CardBus PC Card Power Management
The PCI1210 implements its own card power management engine that can be used to turn off the CCLK to the
socket when there is no activity to the CardBus PC Card. The PCI CCLKRUN protocol is followed on the
CardBus interface to control this clock management.
16-Bit PC Card Power Management
The COE and PWRDOWN bits in the ExCA registers are provided for 16-bit PC Card power management. The
COE bit three states the card interface to save power. The power savings when using this feature are minimal.
The COE bit will reset the PC Card when used, and the PWRDOWN bit will not. Furthermore, the PWRDOWN
bit is an automatic COE, that is, the PWRDOWN performs the COE function when there is no card activity.
NOTE:
The 16-bit PC Card must implement the proper pullup resistors for the COE and PWRDOWN
modes.
38
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265