AMD SB600 Technical Reference Manual page 220

Field Name
Modem send out through
DMA2 enable
Modem send out through
DMA3 enable
Status To Mem
Modem_slots_alloc_1
Reserved
In DMA enable
Out DMA #1 enable
Out DMA #2 enable
Out DMA #3 enable
Reserved
Audio present
Reserved
Gpio through DMA en
Loop back enable
Packed format disable
Burst enable.
Panic enable
Modem_slots_alloc_0
AC Link active
AC'97 software reset
AC97 Sync
AC97 Reset#
©2008 Advanced Micro Devices, Inc.
AMD SB600 Register Reference Manual
Modem Command - RW - 32 bits - [MEM_Reg: 08h]
Bits Default
3 0b
4 0b
5 0b
6 0h
7 0h
8 0b
9 0b
10 0b
11 0b
19:12 00h
20 0b
21 0b
22 0b
23 0b
24 0b
25 0b
26 0b
27 0b
28 0b
29 0b
30 0b
31 0b
Description
Enables sending of modem data to slot 10 on AC link
using out DMA2
Enables sending of modem data to slot 11 on AC link
using out DMA3
When reg0x04[1] is enabled, after finishing an input or
output modem DT data block, the status will be
updated in either DT memory or in reg0x00.
0: Update status to register
1: Update status to memory
Refer to Modem_slots_alloc_0 (bit 27 of this register)
for more detailed information.
Enables input DMA
Enables output DMA 1
Enables output DMA 2
Enables output DMA 3
1 - Audio is present;
0 - Audio is not present (for Modem driver), set by
BIOS [Read-only]
1 - Gpio data (slot 12) comes from DMA 3 along with
data for slot 11.
0 - Gpio data (slot 12) comes from Gpio register 74h.
Enables loop-back mode. The SDATA_OUT
connected directly to the SDATA_IN
1 - Disable packed format for sending data: data is
sent to memory including data from Slot1 and 2
(physical address and data are sent to memory along
with other data).
0 - Data sent to memory through DMA in packed
format, no slot 1 and 2 - default
Enables Burst operation: Will send/request data only
based on threshold value & overflow condition.
Enables panic signal - to get more priority over internal
bus.
Once this bit is set to 1, writing 0 to it has no effect.
{Modem_slots_alloc_1, Modem_slots_alloc_0} =
00: Only slot 5 is allocated to the modem.
01: Slots 5 and 12 are allocated to the modem.
10: Slots 5, 10, 11, and 12 are allocated to the
modem.
11: Slots 5, 10, 11, and 12 are allocated to the
modem.
1 - AC Link is in the ACTIVE state.;
0 - AC Link is not in the ACTIVE state. [Read-only]
0 – De-assert ac97 software reset asynchronous to
BIT_CLK
1 – Assert ac97software reset asynchronous to
BIT_CLK. Registers in BIT_CLK domain will be reset.
0 – De-assert AC link's SYNC asynchronous to
BIT_CLK
1 – Assert AC link's SYNC asynchronous to BIT_CLK
1 – De-assert AC link's RESET# asynchronous to
BIT_CLK
0 – Assert AC link's RESET# asynchronous to
BIT_CLK
AC '97 Controller Functional Descriptions
Proprietary Page 220