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Signal Definitions
(Continued)
2.4.15 Power Management Interface Signals
Signal Name
Ball No.
Type
Description
Mux
EBGA
TEPBGA
CLK32
H29
AH8
O
32.768 KHz Output Clock
---
GPWIO0
E31
AH6
I/O
General Purpose Wakeup I/Os.
These sig-
nals each have an internal pull-up of 100 K
.
---
GPWIO1
G28
AK5
---
GPWIO2
G29
AJ6
---
LED#
D31
AL4
O
LED Control.
Drives an externally connected
LED (on, off or a 1 Hz blink). Sleeping /
Working indicator. This signal is an open-
drain output.
---
ONCTL#
E30
AJ5
O
On / Off Control.
This signal indicates to the
main power supply that power should be
turned on. This signal is an open-drain out-
put.
---
PWRBTN#
E29
AH5
I
Power Button.
Input used by the power
management logic to monitor external sys-
tem events, most typically a system on/off
button or switch.
The signal has an internal pull-up of 100 K
,
a Schmitt-trigger input buffer and debounce
protection of at least 16 ms.
ACPI is non-functional when the power-up
sequence does not include using the power
button. If ACPI functionality is desired, the
power button must be toggled. This can be
done externally or internally. GPIO63 is inter-
nally connected to PWRBTN#. To toggle the
power button with software, GPIO63 must be
programmed as an output using the normal
GPIO programming protocol (see Section
5.4.1.1 "GPIO Support Registers" on page
231). GPIO63 must be pulsed low for at least
16 msec and not more than 4 sec. Asserting
POR# has no effect on ACPI. If POR# is
asserted and ACPI was active prior to POR#,
then ACPI will remain active after POR#.
Therefore, BIOS must ensure that ACPI is
inactive before GPIO63 is pulsed low.
---
PWRCNT1
F31
AK6
O
Suspend Power Plane Control 1 and 2.
Control signal asserted during power man-
agement Suspend states. These signals are
open-drain outputs.
---
PWRCNT2
G31
AL7
O
---
THRM#
F28
AK4
I
Thermal Event.
Active low signal generated
by external hardware indicating that the sys-
tem temperature is too high.
---