307013-003 Datasheet, PDF (733/848 Pages) Intel Corporation – Intel I/O Controller Hub 7

Intel® High Definition Audio Controller Registers (D27:F0)
19.2.4
OUTPAY—Output Payload Capability Register
(Intel^® High Definition Audio Controller—D27:F0)
Memory Address:HDBAR + 04h
Default Value: 003Ch
Attribute:
Size:
RO
16 bits
19.2.5
Bit
Description
15:7
6:0
Reserved.
Output Payload Capability — RO. Hardwired to 3Ch indicating 60 word payload.
This field indicates the total output payload available on the link. This does not include
bandwidth used for command and control. This measurement is in 16-bit word
quantities per 48 MHz frame. The default link clock of 24.000 MHz (the data is double
pumped) provides 1000 bits per frame, or 62.5 words in total. 40 bits are used for
command and control, leaving 60 words available for data payload.
00h = 0 word
01h = 1 word payload.
.....
FFh = 256 word payload.
INPAY—Input Payload Capability Register
(Intel^® High Definition Audio Controller—D27:F0)
Memory Address:HDBAR + 06h
Default Value: 001Dh
Attribute:
Size:
RO
16 bits
Bit
Description
15:7
6:0
Reserved.
Input Payload Capability — RO. Hardwired to 1Dh indicating 29 word payload.
This field indicates the total output payload available on the link. This does not include
bandwidth used for response. This measurement is in 16-bit word quantities per 48
MHz frame. The default link clock of 24.000 MHz provides 500 bits per frame, or 31.25
words in total. 36 bits are used for response, leaving 29 words available for data
payload.
00h = 0 word
01h = 1 word payload.
.....
FFh = 256 word payload.
Intel ^® ICH7 Family Datasheet
733