Seagate Travan 40, Product Manual

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ATAPI Interface Chapter 5
Seagate Travan 40 Product Manual Page 37
LOG SENSE (Group 2, Op. Code 4D)
The LOG SENSE command provides a means for the Initiator to retrieve statistical
information maintained by the tape drive about the tape drive.
CDB for LOG SENSE Command
Data Bits
Byte 7 6 5 4 3 2 1 0 Hex
0 0 1 0 0 1 1 0 1 4D
1 0 0 0 0 0 0 PPC SP 0X
2 PC Page Code XX
3 0 0 0 0 0 0 0 0 00
4 0 0 0 0 0 0 0 0 00
5
6
MSB
Parameter Pointer
LSB
XX
XX
7
8
MSB
Parameter List Length
LSB
XX
XX
9 0 0 0 0 0 0 0 0 00
PPC: The Parameter Pointer Control (PPC) bit shall be set to 0 with the Parameter
Pointer field 0. This will cause all available log parameters for the specified log page
to be returned to the Initiator subject to the specified allocation length. If the PPC bit
is set to 1 or if the PPC is set to 0 with the Parameter Pointer field other than 0, the
command is terminated with
Check Condition status. The Sense Key will be set to
Illegal Request and the additional Sense Code will be set to Invalid Field in CDB .
SP: The Save Parameters bit must be set to 0.
PC: The Page Control field must be set to 01b. This field defines the type of
parameter values to be selected. The Cumulative Values parameter is the only one
supported.
Page Code: The Page Code field indicates which page of log data is being
requested. The supported Page Codes are:
Code Page Description Ref Page
00h Supported Log Pages 38
03h Error Counter For Read 38
2Eh TapeAlert if enabled via Log Select page 32,
byte 17, bit 7) 40
31h Tape Capacity, Special Information) 45
3Eh Firmware Checksum 49
Parameter Pointer: Shall be set to 0. See PPC.
Parameter List Length: Specifies the number of bytes allocated for Log data. The
number of bytes returned in the Data-In Phase will be the lesser of the Parameter
List Length or the data available in the specified page.