Marantz SA-12S1, Руководство по обслуживанию

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The block also handles overspeed processing for
all systems. The capturing of CD-DA sectors is
based on a flywheel tiner to improve robusters by
concealing erros in the subcode stream. For DVD
the data, having had sector headers removed, then
passes through a DVD conformant de-cryption
stage and is written into any of the system memo-
ries using a programmable DMA engine. When a
subcode stream is present it is locally buffered, by
subcode block and can be read by the CPU for
subsequent processing, if required.
III.7 - PWM and counter module
This unit includes three separate pulse width
modulator (PWM) generators using a shared
counter, and three timer compare and capture
channels sharing a second counter.
The counters can be clocked from a pre-scaled
internal clock or from a pre-scaled external clock
via the capture clock input and the event on which
the timer value is captured is also programmable.
The PWM counters are 8-bit with 8-bit registers to
set the output high time. The capture/compare
counter and the compare and capture registers are
32-bit.
III.8 - Parallel Programmable IO module
40 bits of parallel I/O are provided. 34 of then are
connected to actual PIO pins. Each bit is program-
mable as an output or an input. The output can be
configured as a totem pole or open drain driver. Input
compare logic is provided which can generate an
interrupt on any change on any input bit.
Many pins of the STi5505 device are multi-function
and can either be configured as PIO or connected
to an internal peripheral signal.
III.9 - MPEG Video decoder
The video decoder is a real-time video compres-
sion processor supporting the MPEG-1 and MPEG-
2 standards at video rates up to 720 x 480 x 60 Hz
and 720 x 576 x 50 Hz. Picture format conversion
for display is performed by vertical and horizontal
filters. User-defined bitmaps may be superimposed
on the display picture through use of the on-screen
display function.
III.10 - PAL/NTSC encoder
The digital encoder which is integrated in the STi5505
converts a multiplexed 4:2:2 YUV stream into a
standard analog baseband PAL/NTSC signal and
into RGB analog components. The encoder can also
perform closed-caption, CGMS or teletext encoding
and allows Macrovision
TM
7.01/6.1 copy protection.
III.11 - MPEG-2 Audio / Dolby AC-3 Decoder
The audio decoder is a Dolby AC-3 decoder capable
of decoding both 5.1 and 2 channel DVD comfor-
mant bitstreams. The decoder also handles MPEG-
1 (layers 1 & 2) and MPEG-2 layer 2 (6 channels).
Downmix to 2 channels is possible for Dolby and
MPEG standards with optional pro-logic encoding.
The decoder directly accepts MPEG-2 PES streams
as input. The decoder is capable of supporting
IEC6958-IEC61937 formatted outputs for AC-3 and
MPEG audio, linear PCM (left & right,16, 18, 20 &
24 bits), zero output (Mute mode) and PCM audio.
III - FUNCTIONAL DESCRIPTION (continued)
STi5505 (Rev. Ax)