beautypg.com

2 invert signal polarity (invert_a) bit 6, 3 invert signal polarity (invert_b) bit 5, Figure 18. atapi block diagram – Cirrus Logic CS4398 User Manual

Page 31: Cs4398

background image

DS568F1

31

CS4398

7.3.1

Channel B Volume = Channel A Volume (VOLB=A) Bit 7

Function:

When set to 0 (default), the AOUTA and AOUTB volume levels are independently controlled by the A and
the B Channel Volume Control Bytes.

When set to 1, the volume on both AOUTA and AOUTB are determined by the A Channel Attenuation and
Volume Control Bytes, and the B Channel Bytes are ignored.

7.3.2

Invert Signal Polarity (Invert_A) Bit 6

Function:

When set to 1, this bit inverts the signal polarity of channel A.

When set to 0 (default), this function is disabled.

7.3.3

Invert Signal Polarity (Invert_B) Bit 5

Function:

When set to 1, this bit inverts the signal polarity of channel B.

When set to 0 (default), this function is disabled.

7.3.4

ATAPI Channel Mixing and Muting (ATAPI4:0) Bits 4-0

Default = 01001 - AOUTA=aL, AOUTB=bR (Stereo)

Function:

The CS4398 implements the channel-mixing functions of the ATAPI CD-ROM specification. Refer to Ta-
ble and Figure 18 for additional information.

Figure 18. ATAPI Block Diagram

Σ

Σ

A Channel

Volume

Control

AoutA

AoutB

Left Channel

Audio Data

Right Channel

Audio Data

B Channel

Volume

Control

MUTE

MUTE