STAC9708 datasheet(17/56 Pages) ETC

17 / 56 page

SigmaTel, Inc.

Preliminary

STAC9708/11

10/02/98

3.1.1.2 Slot 2: Command Data Port

The command data port is used to deliver 16-bit control register write data in the event that

the current command port operation is a write cycle. (as indicated by Slot 1, bit 19)

Bit (19:4)

Control Register Write Data

(Stuffed with 0's if current operation is a read)

Bit (3 :0)

Reserved

(Stuffed with 0's)

If the current command port operation is a read then the entire slot time must be stuffed with

0's by the AC'97 controller.

3.1.1.3 Slot 3: PCM Playback Left Channel

Audio output frame slot 3 is the composite digital audio left playback stream. In a typical

“Games Compatible" PC this slot is composed of standard PCM (.wav) output samples

digitally mixed (on the AC'97 controller or host processor) with music synthesis output

samples. If a sample stream of resolution less than 20-bits is transferred, the AC'97 controller

must stuff all trailing non-valid bit positions within this time slot with 0's.

3.1.1.4 Slot 4: PCM Playback Right Channel

Audio output frame slot 4 is the composite digital audio right playback stream. In a typical

“Games Compatible" PC this slot is composed of standard PCM (.wav) output samples

digitally mixed (on the AC'97 controller or host processor) with music synthesis output

samples. If a sample stream of resolution less than 20-bits is transferred, the AC'97 controller

must stuff all trailing non-valid bit positions within this time slot with 0's.

3.1.1.5 Slot 5: Reserved

Audio output frame slot 5 is reserved for modem operation and is not used by the

STAC9708/11.

3.1.1.6 Slot 6: PCM Center Channel

Audio output frame slot 6 is the composite digital audio center stream used in a multi-channel

application where the STAC9708/11 is programmed to accept the primary DAC PCM data

from slots 6 and 9. As a programming option, PCM data from slots 6 and 9 may be used to

supply data to the surround DACs when slots 7 and 8 are used to drive the primary DACs.

Please refer to the register programming section for details on the multi-channel programming

options.

STAC9708 Datasheet(PDF) 17 Page - List of Unclassifed Manufacturers