Vela 2000-0600, Инструкция по установке и эксплуатации

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Chapter 2 — Decoder Command Set Guide 99
MODE SENSE (6)
The following table shows LTC output during trick modes (For GOP header or
firmware generated time codes).
Audio Level Mode Page (35h)
This page is not supported.
Mode Sense Example
The Mode Sense returns the requested Mode page along with one or two addition-
al headers. A Mode Sense always returns a four-byte Mode Parameter Header.
Also, when the DBD bit of the Mode Sense is zero, an eight-byte Block Descrip-
tor is also returned. To read back Mode Page 30h (Vela MPEG Decoder status
Page), the total amount of returned data will be as follows (when DBD = 0).
A total of 32 bytes will be returned.
Trick Mode LTC Output Function
Stop LTC output, last valid time code.
Play LTC output. each video frame will have a new time code.
Pause LTC output, same time code repeated each video frame sync
until resume.
Frame Advance LTC output, same time code repeated each video frame sync
until frame advance is executed, then time code will increment.
Fast Forward LTC output, approximate time code for the I-frames of the GOP.
This is due to the fact that the MPEG decoder only displays I-
frames in fast forward mode.
Slow Motion LTC output, time code will be output each video frame sync,
but time code value will follow the playback rate. During slow
motion, each picture is displayed several times before advanc-
ing to the next picture.
4 byte Mode Parameter Header
8 byte Mode Parameter Block Descriptor
20 byte Mode Page 0x30