WAET

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The WAET (Windows ACPI Emulated Devices Table) is a table in ACPI running in guest partitions in a virtual machine environment.

For the latest information, see: Microsoft's WAET specifications

ACPI Standard Header	Field	Byte length	Byte offset	Description
✅	Signature	4	0x0	Signature for the WAET
✅	Length	4	0x4	Length, in bytes, of the WAET
✅	Revision	1	0x8	1
✅	Checksum	1	0x9	Entire table, which must sum to zero
✅	OEMID	6	0x10	Original equipment manufacturer (OEM) identifier (ID)
✅	OEM Table ID	8	0x16	Manufacturer model ID
✅	OEM Revision	4	0x24	OEM revision for supplied OEM table ID
✅	Creator ID	4	0x28	Vendor ID of the ASL compiler utility that created the table
✅	Creator Revision	4	0x32	Revision of the ASL compiler utility that created the table
❌	Emulated Device Flags	4	0x36	Container of a bitmask of Windows behavior that this system requires

Bit offset	Description
0	RTC good Indicates whether the RTC has been enhanced not to require acknowledgment after it asserts an interrupt. With this bit set, an interrupt handler can bypass reading the RTC register C to unlatch the pending interrupt.
1	ACPI PM timer good Indicates whether the ACPI PM timer has been enhanced not to require multiple reads. With this bit set, only one read of the ACPI PM timer is necessary to obtain a reliable value.
31:2	Reserved; must return 0 when read.