Commands 95
Commands
READ 08h
READ transfers zero or more data blocks to the host starting at the current
logical position.
Pre-Execution Checks:
If both the SILI and Fixed bits are set, CHECK CONDITION status is reported.
Sense data is as described in the Illegal Field Checks. The field pointers
indicate the Fixed bit field.
Note Transfers of 4 bytes or less are not supported.
Command Descriptor Block:
CDB Fields:
If the Fixed flag is clear and Transfer Length is not zero, then a single block of
the length in Transfer Length is to be transferred. If the next block on tape is of
this length or shorter it is transferred to the initiator. If the next block is longer
than this length, only the length requested is returned and the logical position
is set to after the record. If the length of the block was the same as the Transfer
Length field,
GOOD status is returned. If the length of the block was not the
same as in Transfer Length and the Suppress Illegal Length Indicator (SILI) flag
was clear,
Check Condition status is returned, ILI will be reported as described
below. If the length of the block was not the same as in Transfer Length and the
Suppress Illegal Length Indicator (SILI) flag was set,
Good status is returned.
Illegal Field Fixed Bit Reservation Deferred Error
Unit Attention Media Access Diagnostic Status
7 6 5 4 3 2 1 0
0
Operation Code (08h)
1
Reserved(0) SILI Fixed
2
(MSB)
Transfer Length
4
(LSB)
5
Control
