Write And Verify - HP C2488A Technical Reference Manual

Write And Verify
Write And Verify
The WRITE AND VERIFY command requests the Target to write the data transferred by
the Initiator to the media, and then verify the data that was written.
Write And Verify Command Descriptor Block (COB)
Bit
Byte
7
I
6
I
5
I
4
I
3
I
2
I
1
I
0
00 Opcode = 2EH
01
Logical Unit Number
I
DPO=O
I
Reserved
I
BYTCK
I
ReIAdr=O
02-05
(MSB=02) Logical Block Address (LSB=05)
06 RESERVED
07-08
(MSB=07) Transfer Length (LSB=08)
09 Control Byte
BYTCK (Byte Cheek). If the BYTCK bit is set to zero (0), an ECC verification of the data
written is performed with no data comparison. If BYTCK is set to one (1), the drive will do
a byte-by-byte comparison of the data written to the data read from the media. If the data
does not compare with that on the media, a Status of CHECK CONDITION will be returned.
The Sense Key will be set to MISCOMPARE with a Sense Code of COMPARE ERROR. If
the data cannot be read from the media, a MEDIUM ERROR will be returned.
Logical Block Address. This field specifies the logical block at which the WRITE AND
VERIFY operations will begin.
Transfer Length. This field specifies the number of contiguous logical blocks of data to be
transferred. A Transfer Length of zero in.dicates that no logical blocks shall be transferred.
This condition shall not be considered an error (it is functionally equivalent to a SEEK
command). If the BYTCK bit is set to one (1), the total number of bytes to be written and
verified must not exceed 32,768 or the following will be returned:
DRAFT
1/18/93 09:58
Status: CHECK CONDITION
Sense Key: ILLEGAL REQUEST
Sense Code: ILLEGAL FIELD IN CDB
SCSI Command Descriptions A-59