Seagate Technology 10002475-003, Product Description Manual

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ATAPI Interface Chapter 5
Product Description Manual Page 45
The Remaining Capacity for noncurrent partitions shall be the same as the
Maximum Capacity for that partition. Capacities are multiplied by 1024 to
determine the number of bytes. These values are conservative estimates.
The Parameter bit, TSD (not shown), is zero implying that the drive can save
parameters across resets, etc. Parameters are not saved but are recomputed
correctly from any logical position, regardless of the previous states of the tape
drive.
Mode Select
Bit
Byte
7 6 5 4 3 2 1 0
0 Operation code (15h)
1 Reserved 1 (PF) Reserved
2 Reserved
3 (MSB) Parameter List Length
4 (LSB)
5 Reserved
The Mode Select command provides a means to change device parameters. The
PF (Page Format) bit is 1, since the Mode Pages are in SCSI-2 format. The only
changable parameters are Speed Selection (in the Mode Parameter Header),
and certain fields in Mode Page 2Bh (MFM mode). The Parameter List Length
field specifies the length in bytes of the Mode Select parameter list that are
transferred to the device as data. A Parameter List Length of zero indicates
that no data is transferred.
Mode Sense should be issued prior to Mode Select to determine the supported
pages, page lengths, and other parameters.
The device terminates the Mode Select command with a Check Condition
status, sets the Sense Key to Illegal Request, and sets the Additional Sense
Code to Invalid Field in Parameter List for the following conditions:
z
If an attempt is made to change an unchangable value in the Mode Select
header, block descriptor, or any page.
z If an attempt is made to send a page with a length not equal to the
parameter length reported for that page by the Mode Sense command.
z If an attempt is made to send a value for a parameter that is outside the
range supported by the device.