OEM MANUAL:K6602771
6 COMMAND DESCRIPTIONS
Revision: 2 / Date: 2002.12.19
Page: 238 / 313
6.14 READ CAPACITY:(25
H
)
Bit
Byte
7
6
5
4
3
2
1
0
0
Operation Code (25
H
)
0
0
1
0
0
1
0
1
1
Logical Unit Number
Reserved
RelAdr
0
0
0
0
0
2
Logical Block Address (MSB)
3
Logical Block Address
4
Logical Block Address
5
Logical Block Address (LSB)
6
Reserved
0
0
0
0
0
0
0
0
7
Reserved
0
0
0
0
0
0
0
0
8
Vendor Unique
Reserved
PMI
0
0
0
0
0
0
0
9
Vendor Unique
Reserved
Flag
Link
0
0
0
0
0
0
The READ CAPACITY command requests the controller to transfer the data
concerning the logical unit capacity to the host computer.
The PMI (Partial Medium Indicator) bit of 0 indicates that the logical block address
and block length of the last logical block on the logical unit are to be transferred to
the host computer. In this case, the Logical Block Address in the CDB must be 0.
If this condition is violated, the controller creates the CHECK CONDITION status
with ILLEGAL REQUEST sense key.
The PMI bit of 1 specifies that the controller is to transfer to the host computer the
logical block address and block length of the last logical block starting from the
specified Logical Block Address in the CDB (including the address itself), after which
a substantial delay in data transfer will be encountered.
The delay by interleave or by accessing the sector reassigned using sector slipping for
bad sector alternation is not regarded as substantial.
The controller transfers the eight bytes of read capacity data shown in Table 6-84 in
the Data In phase of the command.
READ CAPACITY:(25h)