Vela CineCast 2000-0422, Инструкция по установке и эксплуатации

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Chapter 2 — Overview and Operation 109
WRITE BUFFER
WRITE BUFFER
(OpCode 3Bh, 10 bytes)
This command is included for downloading new decoder firmware (microcode)
over the SCSI bus to the Quad Pro decoder.
Mode –
Two modes are supported:
• 100b Download microcode without Save
• 101b Download microcode and Save
Buffer ID
Field is ignored.
Buffer Offset
Starting offset of download data; must be zero or a multiple of 8-K bytes.
Parameter List Length
Length of data transfer; must be a multiple of 8-K bytes up to a maximum length
of 1024K.
Programming the Decoder Firmware (Microcode)
The decoder’s microcode consists of 1024K of data which is downloaded via the
WRITE BUFFER
command and saved into the decoder’s non-volatile memory.
The microcode follows the command in the Data-Out phase. The microcode
download can be accomplished via a single 1024-K transfer, sixteen 64-K trans-
fers, 128 8-K transfers, or other combinations of 8-K multiples to load the 1024K.
Table 2-23.WRITE BUFFER Command Format