32579B

Core Logic Module

6.2.9.3Power Planes Control

The SC1200/SC1201 processor supports up to three power planes. Three signals are used to control these power planes. Table 6-6describes the signals and when each is asserted.

Table 6-6. Power Planes Control Signals vs.

Sleep States

 

 

 

 

 

SL4

 

 

 

 

 

and

Signal

S0

SL1

SL2

SL3

SL5

 

 

 

 

 

 

PWRCNT1

1

1

0

0

0

 

 

 

 

 

 

PWRCNT2

1

1

1

0

0

 

 

 

 

 

 

ONCTL#

0

0

0

0

1

 

 

 

 

 

 

These signals allow control of the power of system devices and the SC1200/SC1201 processor itself. Table 6-7describes the SC1200/SC1201 processor’s power planes with respect to the different Sleep and Global states.

Table 6-7. Power Planes vs. Sleep/Global States

 

VCORE,

 

 

Sleep/

VCCCRT, VI/O,

 

 

Global

AVCCTV, VPLL,

VSB, VSBL

VBAT

State

AVCCCRT

S0, SL1 and

On

On

On or Off

SL2

 

 

 

 

 

 

 

SL3, SL4

Off

On

On or Off

and SL5

 

 

 

 

 

 

 

G3

Off

Off

On

 

 

 

 

No Power

Off

Off

Off

 

 

 

 

Illegal

On

Off

On or Off

 

 

 

 

The SC1200/SC1201 processor’s power planes are con- trolled externally by the three signals (i.e., the system designer should make sure the system design is such that Table 6-7is met) for all supported Sleep states.

VSB and VBAT are not controlled by any control signal. VSB exists as long as the AC power is plugged in (for desktop

systems) or the main battery is charged (for mobile sys- tems). VBAT exists as long as the RTC battery is charged.

The case in which VSB does not exist is called Mechanical Off (G3).

6.2.9.4Power Management Events

The SC1200/SC1201 processor supports power manage- ment events that can manage:

Transition of the system from a Sleep state to a Work state. This is done by the hardware. These events are defined as wakeup events.

Enabled wakeup events to set the WAK_STS bit (F1BAR1+I/O Offset 08h[15]) to 1, when transitioning the system back to the working state.

Generation of an interrupt. This invokes the relevant 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 6-8lists the power management events that can gen- erate an SCI or SMI.

Table 6-8. Power Management Events

Event

SCI

SMI

 

 

 

Power Button

Yes

Yes

 

 

 

Power Button Override

Yes

-

 

 

 

Bus Master Request

Yes

-

 

 

 

Thermal Monitoring

Yes

Yes

 

 

 

USB

Yes

Yes

 

 

 

RTC

Yes

Yes

 

 

 

ACPI Timer

Yes

Yes

 

 

 

GPIO

Yes

Yes

 

 

 

SDATA_IN2 (AC97)

Yes

Yes

 

 

 

IRRX1

Yes

Yes

 

 

 

RI2#

Yes

Yes

 

 

 

GPWIO

Yes

Yes

 

 

 

Internal SMI signal

Yes

-

 

 

 

160

AMD Geode™ SC1200/SC1201 Processor Data Book

Page 160
Image 160
AMD SC1200 Power Planes Control Signals vs Sleep States, Power Planes vs. Sleep/Global States, Power Management Events