AMD SB600 User Manual
Page 209
©2008 Advanced Micro Devices, Inc.
AC ’97 Controller Functional Descriptions
AMD SB600 Register Reference Manual
Proprietary
Page 209
Output DMA DT Size and State- R - 32 bits - [MEM_Reg: 48h]
Field Name
Bits
Default
Description
Out DMA DT size
15:0
0000h
Data size of DT for Output DMA.
Reserved 25:16
000h
out DMA state
28:26
0h
Current state of out DMA
Reserved 31:29
0h
Output DMA DT Size & State Register:
SPDIF Command- RW - 32 bits - [MEM_Reg: 4Ch]
Field Name
Bits
Default
Description
Spdif valid bit
0
0b
The value of this bit will go to bit[28] of each enabled sub-frame on
SPDIF_OUT bus, which is the valid bit for that subframe.
Spdif user bit
1
0b
The value of this bit will go to bit[29] of each enabled sub-frame on
SPDIF_OUT bus, which is the user bit for that subframe.
SPDIF bus mute
2
0b
Setting it to 1 will mute the whole SPDIF bus to zero when the next
frame comes. Setting it back to 0 will unmute SPDIF bus when the
next frame comes. Changing of this bit only starts to take effect on
frame boundary.
Reserved 3
0b
LFSR Control
4
0b
0 - Shift direction left.
1 - Shift direction right.
Single channel mode
5
0b
1 - SPDIF operates in the single channel mode (disable second
sub-frame)
0 - SPDIF operates in the 2-channel mode (every sub-frame filed
with data from FIFO)
Reserved
6
0b
Data mute
7
0b
When this bit is set to 1, on each subframe of spdif bus, the data
field (bit[27:4]) is set to 0, no matter what data are written to spdif
FIFO.
LFSR Accumulation
15:8
00h
LFSR Linear feedback shift Register [Read-only]
SPDIF Threshold
20:16
00h
Threshold value for the SPIDF Channel's FIFO. (SPDIF FIFO is
30x28)
Reserved 31:21
000h
SPDIF Command Register: Controls the operation of SPDIF channel.
SPDIF Channel Link List Pointer- RW - 32 bits - [MEM_Reg: 50h]
Field Name
Bits
Default
Description
SPDIF LL ptr enable
0
0b
SPDIF Channel Link List Pointer enable
SPDIF LL Pointer
31:1
0000_0
000h
Pointer to the start of the Link List - to the first DT.
SPDIF Channel Link List Pointer Register: Pointer to the start of Link List for the SPDIF channel.
SPDIF Channel DT Start- R - 32 bits - [MEM_Reg: 54h]
Field Name
Bits
Default
Description
SPDIF DT start
31:0
0000_0
000h
SPDIF Channel Discrete Table (DT) Start Pointer
SPDIF channel DT start Pointer Register: Pointer to the start of data associated with current DT for the SPDIF
channel.
SPDIF Channel DT Next- R - 32 bits - [MEM_Reg: 58h]
Field Name
Bits
Default
Description
SPDIF DT next
31:0
0000_0
000h
Pointer to the next DT for the SPDIF channel.
SPDIF channel Next Pointer Register: