Harman Kardon AVR 140, Service Manual

Page: 97 / 160

2. OVERVIEW
The CS49400 is a 24-bit fixed-point decoder DSP
followed by a 32-bit fixed point programmable
post-processor DSP. The decoder portion of the
CS49400 is referred to as “DSPAB”. The post-
processor DSP is referred to as “DSPC”. Both
DSPAB and DSPC include their own dedicated
peripherals such as serial and parallel control ports,
and serial audio interfaces. DSPC also has a
external
memory interface which supports
SRAM/SDRAM/EPROM.
All the decoding/processing algorithms listed
below require delivery of PCM or IEC61937-
packed compressed data via I2S or LJ formatted
digital audio to the CS49400. Today the CS49400
will
support all of the following
decoding/processing standards:
• PCM Pass-Through/PCM Upsampler
• Dolby Digital
™
(with Dolby Pro Logic)
™
• Dolby Digital Pro Logic II
™
• Dolby Digital EX
™
• Dolby Digital EX Pro Logic II
™
• MPEG-2, Advanced Audio Coding Algorithm
(AAC)
• MPEG Multichannel
• MPEG Multichannel with Dolby Pro Logic II
™
• MPEG-1/2, Layer III (MP3)
• DTS Digital Surround™
• DTS 96/24™ (Front-end Decoder)
• DTS Digital Surround™ with
Dolby Pro Logic II™
• DTS-ES Extended Surround
™
(DTS-ES Discrete 6.1 and DTS-ES Matrix 6.1)
• DTS-ES 96/24
™
(Front-end Decoder)
• DTS Neo:6
™
• LOGIC7
®
• SRS Circle Surround
™
II
• HDCD
®
All of the above audio decoding/processing
algorithms and the associated application notes
(AN208 and their corresponding appendices) are
available through the Crystal Ware
TM
Software
Licensing Program. Please refer to AN208 for the
latest listing of application codes for DSPAB.
DSPC is unique to DSPAB in the sense that the
designer may choose to just load a standard or
enhanced application code (.ULD file) from the
Crystal Ware Software Library or if they have
access
to the Cirrus Framework DSPC
Development Kit, they may choose to build their
own application code from a variety of modules. A
DSPC application code contains all of the
necessary
post-processing modules, such as
Crossbar Mixer, Pro Logic Module, Bass Manager
Module, and Audio Manager (Kernel). A module is
just a single processing module, such as Tone
Control, Parametric/Graphic EQ, or Dolby Pro
Logic matrix decoder. DSPC on the CS49400 will
support the following post-processing application
codes and/or modules:
• Standard Post-Processor (includes the follow-
ing modules all compiled into one .ULD file):
Downmixer module, Dualzone module, Cross-
bar Mixer module, 7.1 Channel Bass Manager
module, Audio Manager module (Volume
Control, Trim Control and Channel Remap),
and Delay module
• Advanced Post-Processor (includes the all of
the standard post-processing modules plus the
Tone Control module, Parametric EQ module,
Re-EQ module in all compiled into one .ULD )
• Dolby Pro Logic
™
• Dolby Pro Logic II
™
• SRS Circle Surround II
™
• DTS Neo:6
™
• LOGIC7
®
• THX
®
Surround EX™ 7.1 Channel
Post-Processor
AVR140 harman/kardon
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