Read Position 34H - Sony AIT-SDX460 Product Specifications Manual

7. ATAPI Packet Command Specification

7.13. READ POSITION 34h

Bit 7
Byte
0
1
2
3
4
5
6
7
8
9
10
9
The READ POSITION command reports the current logical position of the Device. No medium movement shall
occur as a result of the command.
TCLP: The Total Current Logical Position (TCLP) bit of ONE indicates the drive shall return data specifying the
partition, file, and set number with the current logical position. The TCLP bit of ZERO indicates the drive shall
return data specifying the first and last block location with the number of bytes and blocks in buffer.
LONG: The Long Format (LONG) bit of ONE indicates the drive shall return 32 bytes of data. The LONG bit of
ZERO indicates the drive shall return 20 bytes of data.
The LONG bit and the TCLP bit shall be equal. If the LONG and TCLP bits are not equal, or if both the LONG and
the Block Address Type (BT) bits are ONE, the command is rejected with a CHECK CONDITION status and an
ILLEGAL REQUEST sense key set.
BT: The Block Address type (BT) bit controls the content of the short format data. The BT bit if one requests the
drive to return its current First Block Location shall include data block only. The BT bit of ZERO requests the drive
to return the First Block Location as a Logical Block Address (data blocks, File-marks and Save Set Marks are
counted.)
The READ POSITION data shown in Table 7-50: Read Position Data Format shall be returned as data after the
command.
Bit 7
Byte
0 BOP EOP
1
2
3
4 (MSB)
5
6
7
8-19
BOP: A Beginning Of Partition bit of one indicates that the Device is at the beginning-of-partition in the current
partition. A BOP bit of zero indicates that the current logical position is not at the beginning-of-partition.
EOP: An End Of Partition bit of one indicates that the Device is positioned between early-warning and end-of-
partition in the current partition. An EOP bit of zero indicates that the current logical position is not between early-
warning and end-of-partition.
Partition Number: reports the partition number for the current logical position.
7-54
6 5
Reserved
Table 7-50: Read Position Data Format, short form
6 5 4
4 3
Operation Code (34h)
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
3 2
Reserved
Partition Number
Reserved
Reserved
Block Address
Reserved
SONY AIT-1Turbo drive SDX-460V series Ver.1.0
READ POSITION
2 1
TCLP LONG
1 0
(LSB)
0
BT