Cirrus Logic CS4341 - Manual (Page 27)

CS4341
DS298F5 27
6.3 TRANSITION AND MIXING CONTROL (ADDRESS 02H)
6.3.1 CHANNEL A VOLUME = CHANNEL B VOLUME (A = B) BIT 7
Default = 0
0 - Disabled
1 - Enabled
Function:
The AOUTA and AOUTB volume levels are independently controlled by the A and the B Channel Vol-
ume Control Bytes when this function is disabled. The volume on both AOUTA and AOUTB are de-
termined by the A Channel Volume Control Byte and the B Channel Byte is ignored when this function
is enabled.
6.3.2 SOFT RAMP AND ZERO CROSS CONTROL (SZCX) BIT 5-6
Default = 10
00 - Immediate Changes
01 - Changes On Zero Crossings
10 - Soft Ramped Changes
11 - Soft Ramped Changes On Zero Crossings
Function:
Immediate Changes
When Immediate Changes is selected all level changes will take effect immediately in one step.
Changes On Zero Crossings
Changes on Zero Crossings dictates that signal level changes, either by attenuation changes or mut-
ing, will occur on a signal zero crossing to minimize audible artifacts. The requested 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 independent-
ly monitored and implemented for each channel.
Soft Ramped Changes
Soft Ramped Changes allows level changes, both muting and attenuation, to be implemented by in-
crementally ramping, in 1/8 dB steps, from the current level to the new level at a rate of 1dB per 8
left/right clock periods.
Soft Ramped Changes on Zero Crossings
Soft Ramped Changes On Zero Crossings dictates that signal level changes, either by attenuation
changes or muting, will occur in 1/8 dB steps 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
independently monitored and implemented for each channel.
7 6 5 4 3 2 1 0
A = B SZC1 SZC0 ATAPI4 ATAPI3 ATAPI2 ATAPI1 ATAPI0
0 1 0 0 1 0 0 1