CS98000-CQ Cirrus Logic, Inc., CS98000-CQ Datasheet - Page 14

• Manufacturer Part Number: CS98000-CQ
• Description: Internet DVD (iDVD) Chip Solution
• Manufacturer: Cirrus Logic, Inc.

anti-tearing logic ensures that currently displayed
frame buffers are not overwritten.
3.10 Audio Processing
Compressed Audio data is read from the DVD disk
into an input FIFO in DRAM. The data is decom-
pressed, then written to a PCM output FIFO, also in
DRAM. Presentation time stamps (PTS) are ex-
tracted from the stream to update the STC, in order
to maintain audio/video synchronization.
The DMA and decompression stages of audio pro-
cessing can be done with a combination of the
DMA unit, DSP and RISC processors. The DSP is
optimized for audio processing, so most common
formats can be handled by the DSP alone, includ-
ing AC-3, MPEG2 audio, and MP3. The DSP has
enough reserve bandwidth to handle the Karaoke
echo-mix and pith shift, and AC-3 down-mix func-
tions.
The audio output data is written into a DRAM
FIFO in 16, 18 or 20 bit PCM format. A flexible au-
dio output stage can simultaneously output 8 chan-
nels of PCM data to audio DAC’s, or 6 channels of
audio data plus an IEC-958 encoded output, at up
to 96 KHz. The audio interface also includes a flex-
ible PCM input interface, which can input a wide
range of protocols from an audio ADC or IEC-958
receiver.
3.11 Soft Modem
The soft modem processing is handled by one of
the RISC processors, which is typically dedicated
for that function. Data rates up to 56 K (V.90 pro-
tocol) are supported. The CS98000 interfaces to a
simple external CODEC/DAA circuit using a flex-
ible serial interface. The serial interface is a fully
programmable, bi-directional interface and can be
used either as a PCM interface or as an AC97 inter-
face. In PCM mode, the sample size could be ad-
justed to 20, 18 or 16 bits to match common DAC
and ADC formats, or any other specific size. In
14
AC97 mode, any slot can be used to interface either
a modem CODEC or an audio CODEC.
3.12 Video
The Digital Video Interface provides flexible and
powerful means of outputting digital video data to
external devices in CCIR601/3 and CCIR656 YUV
formats.
NTSC/PAL video encoder, in both master and
slave sync configurations. The internal frame buff-
er format could be 4:2:0, 4:2:2, YUV655, RGB565
and RGB555. Cirrus Logic provides some easy to
use utilities in order to get the best advantage of the
powerful video filtering capabilities of the
CS98000.
NTSC/PAL video decoder input interface. The in-
terface accepts CCIR, CIF, and QCIF formats, out
of many TV decoders on the market. The video
processor also allows multiple video plans overlay
(main video / video input / picture_in_picture /
on_screen display / cursor). CS98000 has been
proven to work with many TV encoders on the
market with brands, such as, Crystal, Brooktree,
ADI, and AVS.
The Video Input Scaler (VIS) module inputs 8-bit
digital video data from a camera or PAL/NTSC de-
coder, optionally down-scales to SIF or QSIF, and
stores the data in one to three DRAM frame buff-
ers. The scaled image, with a border, can be over-
layed anywhere on the screen into a ½ or ¼-screen
sized window by the Picture in Picture (PIP) mod-
ule.
An alternate method of using the Video Input func-
tion is to input a full sized picture, and present it on
the screen full size (bypass mode). In this mode, the
PIP module can place full motion DVD images in
the small window. An internal glitch-free mux can
switch the video processor clock source from the
internal clock to the Video Input clock, allowing
the PIP mode to switch back and forth on the fly,
with no dropout.
The
The
interface
CS98000
directly
also
CS98000
features
DS525PP1
supports
an