Seagate STT20000A, Руководство по эксплуатации продукта

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Chapter 5 ATAPI Interface
Page 50 STT20000A Product Manual
Mode Sense command
Bit
Byte
7 6 5 4 3 2 1 0
0 Operation code (1Ah)
1 Reserved DBD Reserved
2 00(PC) Page Code
3 (MSB) Allocation Length
4 (LSB)
5 Reserved
The PC (Page Control) field is 00, since only current values are reported. If DBD
(Disable Block Descriptor) is set (1), then the Mode Block Descriptor is not included
in the data returned to the host. The Allocation Length field specifies the number of
data bytes to transfer
The following pages are supported for Mode Select and Mode Sense commands.
Page Code Description
11h Medium Partition Page
2Ah Capabilities and Mechanical Status Page
2Bh Tape Parameters Page (MFM mode)
3Fh Return All Pages
Mode Parameter Header
The following table describes the Mode Parameter header.
Byte Description Value Meaning
0 Mode Data Length NN Select: Reserved
Sense: Length of Available Following Data
1 Medium Type NN Tape type
2 Device Specific Parameters WP,001,Speed Bit 7 = Write Protect, Bits 6-4 = 001, Bits 3-
0 = Speed Selection
3 Block Descriptor Length 00/08h If 8, Block Descriptor follows