CS4341

DS298PP2

19

Soft Ramp and Zero Cross Enable

Soft Ramp and Zero Cross Enable dictates that signal level changes, either by attenuation changes

or muting, will occur in 1/8 dB steps and be implemented on a signal zero crossing. The 1/8 dB level

change will occur after a timeout period between 512 and 1024 sample periods (10.7 ms to 21.3 ms

at 48 kHz sample rate) if the signal does not encounter a zero crossing. The zero cross function is

indepently monitored and implemented for each channel.

4.9

ATAPI CHANNEL MIXING AND MUTING

Volume and Mixing Control Register (address 02h)

Access:

Default:

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

Function:

The CS4341 implements the channel mixing functions of the ATAPI CD-ROM specification. Refer to

Table 9 and Figure 28 for additional information.

SOFT

ZERO

Mode

0

0

Changes to affect immediately

0

1

Zero Cross enabled

1

0

Soft Ramp enabled

1

1

Soft Ramp and Zero Cross enabled

Table 8. Soft Ramp and Zero Cross Enable

765

4321

0

A = B

Soft

Zero Cross

ATAPI4

ATAPI3

ATAPI2

ATAPI1

ATAPI0

ATAPI4

ATAPI3

ATAPI2

ATAPI1

ATAPI0

AOUTA

AOUTB

0000

0

MUTE

MUTE

0000

1

MUTE

bR

0001

0

MUTE

bL

0001

1

MUTE

b[(L+R)/2]

0010

0

aR

MUTE

0010

1

aR

bR

0011

0

aR

bL

0011

1

aR

b[(L+R)/2]

0100

0

aL

MUTE

0100

1

aL

bR

0101

0

aL

bL

0101

1

aL

b[(L+R)/2]

0110

0

a[(L+R)/2]

MUTE

0110

1

a[(L+R)/2]

bR

0111

0

a[(L+R)/2]

bL

0111

1

a[(L+R)/2]

b[(L+R)/2]

1000

0

MUTE

MUTE

1000

1

MUTE

bR

Table 9. ATAPI Decode