Vela 2000-0600, Инструкция по установке и эксплуатации

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44 CineCast HD Version 2.6 Installation and User Manual
To enable all commands, the following sequence must be performed:
INQUIRY
TEST UNIT READY
(Will report check condition)
REQUEST SENSE
TEST UNIT READY
(Optional, will report Good status)
This command sequence is typically performed automatically by the SCSI host
adapter (initiator) during power-up. Following the above sequence, all decoder
commands will be active.
SCSI Command Description
The following command descriptions contain detailed information on the SCSI
commands that are supported by the CineCast HD decoder.
Command fields within SCSI Command Descriptor Blocks are supported as
follows:
Logical Unit Number (LUN)
Ignored by the decoder. Per SCSI-2 recommendations this field should be set to
0. This field was used for SCSI-1 devices, but is now reserved. SCSI-2 requires
Logical Unit Number to be specified in the Identify message, not in this field.
Reserved
Reserved bits, fields, bytes, and code values are set aside for future standardiza-
tion and must be set to zero. If the decoder receives a command that contains
non-zero bits in a reserved field or a reversed code value, the command is termi-
nated with a Check Condition status. The sense key (read via a
REQUEST SENSE
)
is set to
ILLEGAL REQUEST
.
Control
The control byte is the ending byte of all SCSI Command Descriptor Blocks and
has the following format:
NOTE: The control byte of each SCSI command must be zero. Linked commands are
not supported by the decoder.
7 6 5
Reserved Flag Link Vendor Specific
4 3 2 1 0
0
Bit
Byte
Table 2-2. Control Byte Format