Toshiba TDP-D1, Service Manual

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85
Clocks
Carefully chose the crystal for the video decoder. Use the crystal specified on the decoder
manufacturer’s data sheet. A crystal that operates at the correct frequency is critical for proper video
decoding.
Output Signals
Use series terminating resistors on the clock, sync, and data outputs of the Video Decoder to
greatly reduce EMI effects. These resistors reduce the amount of current the Video Decoder must
source for these signals, which may increase its accuracy. Place the resistors as close to the source as
possible, because there are up to 24 bits of data. Route these signals as directly as possible. If the
decoder supports 16-bit YUV, use this mode instead of the 24-bit RGB. The 16-bit YUV mode uses
fewer signals and has the same signal quality. Video Decoders have 2X or 1X output clocks. If a 2X
clock is used, another signal (DEN) is required to indicate which phase of the 2X clock to use. Some
Video Decoders have built-in image scaling capability. To take advantage of this capability, connect
the DEN output from the Video Decoder to the VPEN input of the ImageProcessor so that the
ImageProcessor knows which output pixels are valid.
Microprocessor Interface
This section provides design guidelines for the Microprocessor interface, and describes:
 Read

-Only Memory (ROM)
 External SRAM (Optional)

 Nonvolatile RAM

 Debugger Interface

 ROM Emulator Connector

 Reset and NMI
