SPD6729QCE Intel, SPD6729QCE Datasheet - Page 29

• Manufacturer Part Number: SPD6729QCE
• Description: PCI To PC Card (PCMCIA) Controller 208-Pin MQFP
• Manufacturer: Intel

Specifications of SPD6729QCE

• Package: 208MQFP
• Operating Temperature: 0 to 70 °C

3.1.4.4
3.1.5
Datasheet
Note: Interrupt and General Control register bits 5 and 7 must be set to ‘1’s for a socket interface to
PCMCIA cards with differing I/O functionalities to be connected to appropriate non-conflicting
IRQ locations, the PD6729 can steer the interrupt signal from a PCMCIA card to any one of the ten
different hardware interrupt lines.
For some I/O-type cards, software is written so that IRQ interrupts can be shared. The PD6729
contains unique logic that allows IRQ-type interrupts to be shared under software control. This is
accomplished by programming the PD6729 to alternately pulse and then three-state the desired
interrupt pin, which has been programmed as an IRQ-type output. This unique IRQ interrupt
sharing technique can be controlled through software so that systems incapable of IRQ sharing
have no loss of functionality.
Alternate Functions of Interrupt Pins
The PD6729 has two dual-function interrupt pins: IRQ14/EXT_CLK and IRQ15/RI_OUT*. In
their default modes, these pins indicate interrupt requests IRQ14 and IRQ15.
IRQ14/EXT_CLK can alternately be configured as an external clock input (EXT_CLK). When
configured in External Clock mode by programming Misc Control 2 register bit 0 to a ‘1’, IRQ14/
EXT_CLK acts as a clock input, bringing in an external clock that drives the PD6729 circuitry
whenever the PCI bus is inactive.
Similarly, IRQ15/RI_OUT* can alternately be configured to function as a ring indicator output
(RI_OUT*) to an 80360-type chip set’s -RI input. When configured in Ring Indicate mode by
programming Misc Control 2 register bit 7 to a ‘1’, outputs from a PCMCIA I/O card’s -STSCHG
pin are passed through to the IRQ15/RI_OUT* pin of the PD6729.
accept an -RI input.
PD6729 Power Management
To provide the longest possible battery life, the PD6729 provides many power management
features, including Low-power Dynamic mode, Suspend mode, and control of PCMCIA socket
power.
Low-power Dynamic mode is transparent to the PCI bus. After reset, the PD6729 is configured for
Low-power Dynamic mode. This mode can be turned off by setting Misc Control 2 register, bit 1
to a ‘0’. When in Low-power Dynamic mode, periods of inactivity (no activity on the PCMCIA bus
and system accesses to chip registers or inserted cards are no longer being performed) cause the
PD6729 to enter a low-power state where the clock is turned off to most of the chip and the
PCMCIA address and data lines are set to a static value. V
unchanged. When there is activity present on the PCMCIA bus, or the system accesses PD6729
registers, or PCMCIA cards are inserted or removed from the socket, the PD6729 enters its active
state, services the transaction, and then returns to its low-power state.
A Suspend mode can also be programmed. The PD6729 Suspend mode is the chip’s lowest power
mode. The PD6729 is put into Suspend mode by setting the Misc Control 2 register, bit 2 to a ‘1’.
In Suspend mode, all the internal clocks are turned off, and only read/write access to the PCI-
Configuration registers, read/write access of the Index register, and write access to the Misc
Control 2 register is supported. All accesses to the PCMCIA cards are ignored when in Suspend
mode. V
responsible for turning off power to the socket and entering Suspend mode). Interrupts are passed
through to the processor when in Suspend mode. To exit Suspend mode, the Misc Control 2
register bit 2 must be reset to a ‘0’.
CC
and V
PP
power to the card is left unchanged (the system power management software is
PCI-to-PC Card (PCMCIA) Controller — PD6729
CC
and V
PP
power to the card is left
29