alc880 Realtek Semiconductor Corporation, alc880 Datasheet - Page 29

• Manufacturer Part Number: alc880
• Description: 7.1 Channel High Definition Audio Codec
• Manufacturer: Realtek Semiconductor Corporation

7.4. Verb and Response Format
7.4.1.
There are two types of verbs: one with 4-bit identifiers (4-bit verbs) and 16-bits of data, the other with
12-bit identifiers (12-bit verbs) and 8-bits of data. Table 10 shows the 4-bit verb structure of a command
stream sent from the controller to operate the codec. Table 11 is the 12-bit verb structure that gets and
controls parameters in the codec.
7.4.2.
There are two types of response from the codec to the controller. Solicited Responses are returned by the
codec in response to a current command verb. The codec will send Solicited Response data in the next
frame, without regard to the Set (Write) or Get (Read) command. The 32-bit response is interpreted by
software, opaque to the controller.
Unsolicited Responses are sent by the codec independently of software requests. Jack Detection or GPI
status information can be actively delivered to the controller and interpreted by software. The ‘Tag’ in
Bit[31:28] is used to identify unsolicited events. This tag is undefined in the HDA specifications.
7.1 Channel High Definition Audio Codec
Command Verb Format
Response Format
Note: The response stream in the link protocol is 36-bits wide. The response is placed in the
lower 32-bit field. Bit-35 is a ‘Valid’ bit to indicate the response is ‘Ready’. Bit-34 is set to
indicate that an unsolicited response was sent.
Bit [35]
Bit [39:32]
Bit [39:32]
Reserved
Reserved
Valid
Bit [35]
Valid
Table 11. 40-Bit Commands in 12-Bit Verb Format
Table 10. 40-Bit Commands in 4-Bit Verb Format
Unsol=1
Bit [34]
Codec Address
Codec Address
Table 13. Unsolicited Response Format
Bit [31:28]
Bit [31:28]
Table 12. Solicited Response Format
Unsol=0
Bit [34]
Bit [33:32]
Bit [27:20]
Reserved
Bit [27:20]
Node ID
Node ID
Bit [33:32]
19
Reserved
Bit [19:8]
Bit [19:16]
Verb ID
Verb ID
Bit [31:28]
Tag
Track ID: JATR-1076-21
Bit [31:0]
Response
Bit [15:0]
Bit [7:0]
Payload
Payload
Bit [27:0]
Response
ALC880 Series
Datasheet
Rev. 1.4