Specifications

QSSC-S4R Technical Product Specification Operating System Boot, Sleep, and Wake
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19.4.2 Wake Events / SCI Sources
The server board supports the following wake-up sources in the ACPI environment. The OS controls the enabling and
disabling of these wake-up sources:
x Devices that are connected to any USB port, such as USB mice and keyboards, can wake the system from the S1
sleep state.
x The serial port can be configured to wake the system from the S1 sleep state.
x PCI cards, such as LAN cards, can wake the system from the S1 or S5 sleep state. The PCI card must have the
necessary hardware and be configured correctly for this to work.
x As required by the ACPI specification, the power button can wake the system from all sleep states (S1-S5).
19.5 Non-Maskable Interrupt (NMI) Handling
Non-maskable interrupts are generated by two sources: when the front panel NMI button is pressed, or by the BIOS
detection of a fatal system error. The BIOS installs a default NMI handler that displays a system error message and
then halts the system. The BIOS NMI handler is active during POST and the OS installs its own handler to handle NMI
during OS runtime.
When the BIOS NMI handler is active (such as in DOS), the BIOS handler detects the source of the NMI and displays a
system error message before halting the system. The following table displays the possible error messages.
Table 146. NMI Error Messages
NMI Source S
y
stem Error Message
FP NMI button Front Panel NMI activated - S
y
stem Halted.
S
y
stem Error NMI NMI has been received - S
y
stem Halted.