Chapter1
Motherboard Description
1-10
Speaker Connector
An offboard speaker can be installed on the motherboard as a manufacturing
option. An offboard speaker can be connected to the motherboard at the front
panel connector. The speaker (onboard or offboard) provides error beep code
information during the Power On Self-Test when the computer cannot use the
video interface. The speaker is not connected to the audio subsystem and does not
receive output from the audio subsystem.
Hard Drive LED Connector
This connector can be connected to an LED to provide a visual indicator that data
is being read from or written to a hard drive. For the LED to function properly, an
IDE drive must be connected to the onboard hard drive controller.
Reset Button
This connector can be connected to a momentary SPST type switch that is
normally open. When the switch is closed, the motherboard resets and runs the
POST.
IrDA (Infrared) Connector
After the IrDA interface is configured, files can be transferred from or to portable
devices such as laptops, PDAs, and printers using application software.
Power LED Connector
This connector can be connected to an LED that will light when the computer is
powered on.
Power On Button
This connector can be connected to a front panel power switch. The switch must
pull the Power Button pin to ground for at least 50 ms to signal the power supply
to switch on or off. (The time requirement is due to internal debounce circuitry on
the motherboard.) At least two seconds must pass before the power supply will
recognize another on/off signal.
Sleep /Resume Switch Connector
When APM is enabled in the system BIOS, and the operating system’s APM
driver is loaded, the system can enter sleep (standby) mode in one of the
following ways:
Optional front panel sleep/resume button
Prolonged system inactivity using the BIOS inactivity timer feature
