307013-003 Datasheet, PDF (77/848 Pages) Intel Corporation – Intel I/O Controller Hub 7

Signal Description
Table 2-23. Functional Strap Definitions (Sheet 2 of 3)
Signal
Usage
When
Sampled
Comment
EE_DOUT
(Desktop
and Mobile
Only)
Reserved
This signal has a weak internal pull-up.
NOTE: This signal should not be pulled low.
GNT2#
Reserved
This signal has a weak internal pull-up.
NOTE: This signal should not be pulled low.
GNT3#
Top-Block
Swap
Override
Rising Edge of
PWROK
The signal has a weak internal pull-up. If the signal
is sampled low, this indicates that the system is
strapped to the “top-block swap” mode (Intel^®
ICH7 inverts A16 for all cycles targeting FWH BIOS
space). The status of this strap is readable via the
Top Swap bit (Chipset Configuration
Registers:Offset 3414h:bit 0). Note that software
will not be able to clear the Top-Swap bit until the
system is rebooted without GNT3# being pulled
down.
GNT5# /
GPIO17#,
GNT4# /
GPIO48
Boot BIOS
Destination
Selection
Rising Edge of
PWROK
This field determines the destination of accesses to
the BIOS memory range. Signals have weak
internal pull-ups. Also controllable via Boot BIOS
Destination bit (Chipset Configuration
Registers:Offset 3410h:bit 11:10)
(GNT5# is MSB)
01 = SPI (Desktop and Mobile Only)
10 = PCI
11 = LPC
GPIO16
(Desktop
Only) /
DPRSLPVR
(Mobile/Ultra
Mobile Only)
Reserved
This signal has a weak internal pull-down.
NOTE: This signal should not be pulled high.
GPIO25
DMI AC/DC
Coupling
Selection
(Desktop
Only)
Rising Edge of
RSMRST#
This signal has a weak internal pull-up.The internal
pull-up is disabled within 100 ms after RSMRST#
deasserts.
If the signal is sampled high, the DMI interface is strapped
to operate in DC coupled mode (No coupling capacitors
are required on DMI differential pairs).
If the signal is sampled low, the DMI interface is strapped
to operate in AC coupled mode (Coupling capacitors are
required on DMI differential pairs).
NOTE: Board designer must ensure that DMI
implementation matches the strap selection.
NOTE: The signal must be held low at least 2 us after
RSMRST# deassertion to enable AC coupled
mode.
INTVRMEN
(Desktop
and Mobile
Only)
Integrated
VccSus1_05
VRM
Enable/
Disable
Always
Enables integrated VccSus1_05 VRM when sampled
high.
Intel ^® ICH7 Family Datasheet
77