SC2200 NSC [National Semiconductor], SC2200 Datasheet - Page 169

• Manufacturer Part Number: SC2200
• Description: Thin Client On a Chip
• Manufacturer: NSC [National Semiconductor]

Revision 3.0
Core Logic Module
5.2.9.3
The SC2200 supports up to three power planes. Three sig-
nals are used to control these power planes. Table 5-6
describes the signals and when each is asserted.
These signals allow control of the power of system devices
and the SC2200 itself. Table 5-7 describes the SC2200
power planes with respect to the different Sleep and Global
states.
The SC2200 power planes are controlled externally by the
three signals (i.e., the system designer should make sure
the system design is such that Table 5-7 is met) for all sup-
ported Sleep states.
V
exists as long as the AC power is plugged in (for desktop
systems) or the main battery is charged (for mobile sys-
tems). V
The case in which V
Off (G3).
Table 5-7. Power Planes vs. Sleep/Global States
Sleep/
Global State
S0, SL1 and
SL2
SL3, SL4
and SL5
G3
No Power
Illegal
Signal
PWRCNT1
PWRCNT2
ONCTL#
SB
Table 5-6. Power Planes Control Signals vs.
and V
BAT
Power Planes Control
BAT
exists as long as the RTC battery is charged.
are not controlled by any control signal. V
V
CORE
S0
1
1
0
V
SB
AV
I/O,
Sleep States
CCCRT
On
does not exist is called Mechanical
, V
On
Off
Off
Off
V
PLL
CCCRT
SL1
(Continued)
1
1
0
,
,
SL2
0
1
0
V
V
On
On
Off
Off
Off
SBL
SB
,
SL3
0
0
0
On or Off
On or Off
On or Off
V
On
Off
BAT
SL4
and
SL5
0
0
1
SB
169
5.2.9.4
The SC2200 supports power management events that can
manage:
• Transition of the system from a Sleep state to a Work
• Enabled wakeup events to set the WAK_STS bit
• Generation of an interrupt. This invokes the relevant
Table 5-8 lists the power management events that can gen-
erate an SCI or SMI.
Power Button
The power button (PWRBTN#) input provides two events: a
wake request, and a sleep request. For both these events,
the PWRBTN# signal is debounced (i.e., the signal state is
transferred only after 14 to 16 msec without transitions, to
ensure that the signal is no longer bouncing).
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 internally con-
nected to PWRBTN#. To toggle the power button with soft-
ware, 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
Event
Power Button
Power Button Override
Bus Master Request
Thermal Monitoring
USB
RTC
ACPI Timer
GPIO
SDATA_IN2 (AC97)
IRRX1
RI2#
GPWIO
Internal SMI signal
state. This is done by the hardware. These events are
defined as wakeup events.
(F1BAR1+I/O Offset 08h[15]) to 1, when transitioning
the system back to the working state.
software driver. The interrupt can either be an SMI or
SCI (selected by the SCI_EN bit, F1BAR1+I/O Offset
0Ch[0]). These events are defined as interrupt events.
Table 5-8. Power Management Events
Power Management Events
SCI
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
www.national.com
SMI
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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