Chapter 5 ATAPI Interface
Page 62 Seagate Travan 40 Product Manual
Page Code Description
20h Forced Streaming Page Will Be Returned
2Ah Capabilities and Mechanical Status Page
3Fh All Pages (01h through 3Fh) Will Be Returned
Refer to MODE SELECT command for a description of the Parameter Pages.
Allocation Length: This field specifies the number of bytes requested from the
Parameter List. A maximum of 12 (0Ch) may be returned. When set to 0, no bytes
are transferred and this is not considered an error.
Parameter List: The first four bytes of the Parameter List comprise the Header,
while the remaining bytes comprise the Block Descriptor.
Header Data Bits
Byte 7 6 5 4 3 2 1 0 Hex
0 Sense Data Length XX
1 Media Type XX
2 WP 0 0 BUFM
Speed Code XX
3 Block Descriptor Length 08
Sense Data Length: The Sense Data Length of 11 (0Bh) includes the four-byte
Header and eight-byte Block Descriptor.
Media Type: This byte identifies the cartridge type installed in the drive. 00h
indicates no cartridge or unknown cartridge. See table below for valid cartridge
codes.
Code Cartridge Type
00h No cartridge, cleaning cartridge, or type unknown
85h Travan 5
95h Travan 7
WP: When this bit is 1, the cartridge installed in the drive is Write Protected.
BUFM: The BUFM bit indicates the Buffered Mode is enabled for WRITE
commands. If set to 0, Buffered Mode is disabled for the WRITE command. The
command does not terminate and send a Good Sense until the last data block has
been written onto the tape by the drive. If BUFM is set to 1, the Buffered Mode is
enabled. The WRITE command terminates and returns a Good Status as soon as
the Host places the last data block in the buffer. If an error occurs while writing data
after the command terminates, the drive returns a Check Condition Status on the
next command received from the Host. The Host must then issue a REQUEST
SENSE command to determine the cause of the error. While writing, the drive will
revert to Unbuffered Mode when Logical Early Warning (LEW) is reached. A
REWIND issued at this point will cause the drive to rewind the BOT and return to
Buffered Mode.