STAC9704 datasheet(16/49 Pages) HYNIX

16 / 49 page

SigmaTel, Inc.

STAC9704/7

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 Slots 5-12: Reserved

Audio output frame slots 5-12 are reserved for future use and are always stuffed with 0's by

the AC'97 controller.

3.1.2 AC-link Audio Input Frame (SDATA_IN)

The audio input frame data streams correspond to the multiplexed bundles of all digital input data

targeting the AC'97 controller. As is the case for audio output frame, each AC-link audio input frame

consists of 12, 20-bit time slots. Slot 0 is a special reserved time slot containing 16 bits that are used for

AC-link protocol infrastructure.

STAC9704 데이터시트(PDF) 16 Page - Hynix Semiconductor