Datasheet

Chipset Configuration Registers
Intel® Xeon® Processor D-1500 Product Family 209
Datasheet - Volume 1 of 4: Integrated Platform Controller Hub
March 2015
Note: FEC1_0000h–FEC3_FFFFh is allocated to PCIe when I/OxAPIC Enable (PAE) bit is set.
5.1.35 WADT_AC—Wake Alarm Device Timer – AC Register
Offset Address: 3300–3303h Attribute: R/W
Default Value: FFFFFFFFh Size: 32-bit
5.1.36 WADT_DC—Wake Alarm Device Timer – DC Register
Offset Address: 3304–3307h Attribute: R/W
Default Value: FFFFFFFFh Size: 32-bit
7:0 APIC Range Select (ASEL) — R/W. These bits define address bits 19:12 for the IOxAPIC range.
The default value of 00h enables compatibility with prior Intel® Xeon® Processor D-1500 Product
Family products as an initial value. This value must not be changed unless the IOxAPIC Enable bit is
cleared.
Bit Description
Bit Description
31:0 Wake Alarm Device Timer Value for AC Mode (WADT_AC_VAL): R/W. This field contains the
32-bit wake alarm device timer value (1 second granularity) for AC power. The timer begins
decrementing when written to a value other than FFFFFFFFh (regardless of the power source when
the write occurs). Upon counting down to 0:
• If on AC power, GPE0_STS.WADT_STS will be set. This status bit being set will generate a
host wake if GPE0_EN.WADT_EN is ‘1’.
• If power source is DC at this time, the status bit is not set. However, if AC power subsequently
returns to the platform, the AC Expired Timer begins running. Refer to WADT_EXP_AC for
more details.
• The timer returns to its default value of FFFFFFFFh.
Bit Description
31:0 Wake Alarm Device Timer Value for DC Mode (WADT_DC_VAL): R/W. This field contains the
32-bit wake alarm device timer value (1 second granularity) for DC power. The timer begins
decrementing when written to a value other than FFFFFFFFh (regardless of the power source when
the write occurs). Upon counting down to 0:
• If on DC power, GPE0_STS.WADT_STS will be set. This status bit being set will generate a
host wake if GPE0_EN.WADT_EN is ‘1’.
• If power source is AC at this time, the status bit is not set. However, if DC power subsequently
returns to the platform, the DC Expired Timer begins running. Refer to WADT_EXP_DC for
more details.
• The timer returns to its default value of FFFFFFFFh.
Note: Bits in this register only need to be valid for reading when the Main power well is up.