Datasheet 695
Integrated Intel
®
 High Definition Audio Controller Registers
17.1.1.26 MID—MSI Capability ID Register 
(Intel
® 
High Definition Audio Controller—D27:F0)
Address Offset: 60h–61h Attribute: RO
Default Value: 7005h Size: 16 bits
17.1.1.27 MMC—MSI Message Control Register 
(Intel
® 
High Definition Audio Controller—D27:F0)
Address Offset: 62h–63h Attribute: RO, R/W
Default Value: 0080h Size: 16 bits
1:0
Power State (PS) — R/W. This field is used both to determine the current power state 
of the Intel
®
 High Definition Audio controller and to set a new power state.
00 = D0 state
11 = D3
HOT
 state
Others = reserved
NOTES:
1. If software attempts to write a value of 01b or 10b in to this field, the write 
operation must complete normally; however, the data is discarded and no state 
change occurs.
2. When in the D3
HOT
 states, the Intel
®
 High Definition Audio controller’s configuration 
space is available, but the IO and memory space are not. Additionally, interrupts are 
blocked.
3. When software changes this value from D3
HOT
 state to the D0 state, an internal 
warm (soft) reset is generated, and software must re-initialize the function.
Bit Description
Bit Description
15:8
Next Capability (Next) — RO. Hardwired to 70h. Points to the PCI Express* capability 
structure.
7:0 Cap ID (CAP) — RO. Hardwired to 05h. Indicates that this pointer is a MSI capability.
Bit Description
15:8 Reserved
7
64b Address Capability (64ADD) — RO. Hardwired to 1. Indicates the ability to 
generate a 64-bit message address.
6:4
Multiple Message Enable (MME) — RO. Normally this is a R/W register. However since 
only 1 message is supported, these bits are hardwired to 000 = 1 message.
3:1
Multiple Message Capable (MMC) — RO. Hardwired to 0 indicating request for 1 
message.
0
MSI Enable (ME) — R/W. 
0 = an MSI may not be generated
1 = an MSI will be generated instead of an INTx signal.