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Read 08h, Read 08h 95, Pre-execution checks – HP C737990900 User Manual

Page 95: Command descriptor block: cdb fields

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Commands 95

Co

m

m

an

ds

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