Hitachi HTD-K185UK, Руководство по обслуживанию

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1.2 Memory
SDRAM Memory Interface
The MT1379 provides a glueless 16-bit interface to DRAM memory devices used as
OSD, MPEG stream and video buffer memory for a DVD player. The maximum amount of
memory support is 16 MB of Synchronous DRAM (SDRAM). The memory interface is
configurable in depth to support 128-Mb addressing. The memory interface controls
access to both external SDRAM memories, which can be the sole unified external
read/write memory acting as program and data memory as well as various decoding and
display buffers.
1.3 Drive Interfaces
The MT1379 supports the DV34 interface, and other RF and servo interfaces used
by many types of DVD loaders. These interfaces meet the specifications of many DVD
loader manufacturers.
1.4 Front Panel
The front panel is based around a Futaba VFD and a common NEC front panel
controller chip, (uPD16311). The MT1379 controls the uPD16311 using several control
signals, (clock, data, chip select). The infrared remote control signal is passed directly to
the MT1379 for decoding.
1.5 Rear Panel
A typical rear panel is included in the reference design. This rear panel supports:
• Six channel or two channel audio outputs,
• Optical and coax SPDIF outputs,
• Composite, S-Video, and SCART outputs.
The six-video signals used to provide CVBS, S-Video, and RGB are generated by the
MT1379's internal video DAC, The video signals are buffered by external circuitry.
Six channel audio output by the MT1379 in the form of three I2S (or similar) data
streams. The S/PDIF serial stream is also generated by the MT1379 output by the rear
panel. The six channel audio DACs (AK4356, PCM1606) are used for six channel audio
output with MT1379, and similarly AK4382A, CS4392 Audio DACs are used for two
channel audio output with MT1379.
12-pin DDX board output jack gives out the amplified audio. Digital Audio is processed
in the DDX-8228 IC and then amplified in the DDX-2050 Power Amplifier ICs.