Product Description

1.13.1.2Wake Up Devices and Events

Table 9 lists the devices or specific events that can wake the computer from specific states.

Table 9. Wake Up Devices and Events

These devices/events can wake up the computer…

…from this state

Power switch

RTC alarm

LAN

Modem

USB

PCI bus PME#

S1, S3, S5

S1, S3, S5

S1, S3

S1, S3

S1, S3

S3

1.13.1.3Plug and Play

In addition to power management, ACPI provides controls and information so that the operating system can facilitate Plug and Play device enumeration and configuration. ACPI is used only to enumerate and configure devices that do not have other hardware standards for enumeration and configuration. PCI devices on a desktop board, for example, are not enumerated by ACPI.

1.13.2Hardware Support

CAUTION

If Wake on network event and Instantly Available technology features are used, the power supply must be capable of providing adequate +5 V standby current. Failure to provide adequate standby current can damage the power supply. The total amount of standby current required depends on the wake devices supported and manufacturing options. Refer to Section 2.11.3 on page 54 for additional information.

The board provides several hardware features that support power management, including:

∙Power connector

∙Wake on network event

∙Instantly Available technology

∙Wake on Ring

∙Resume on Ring

Wake on network event and Instantly Available technology require power from the +5 V standby line. The sections discussing these features describe the incremental standby power requirements for each.

Wake on Ring and Resume on Ring enable telephony devices to access the computer when it is in a power-managed state. The method used depends on the type of telephony device (external or internal) and the power management mode being used (ACPI).

✏NOTE

The use of Wake on Ring and Resume on Ring technologies from an ACPI state require the support of an operating system that provides full ACPI functionality.

29