26 Momentus XT Product Manual, Rev. A
4.3.1 Identify Device command
The Identify Device command (command code EC
H
) transfers information about the drive to the host following
power up. The data is organized as a single 512-byte block of data, whose contents are shown in the table on
page 27. All reserved bits or words should be set to zero. Parameters listed with an “x” are drive-specific or
vary with the state of the drive. See Section 2.0 on page 3 for default parameter settings.
The following commands contain drive-specific features that may not be included in the Serial ATA specifica-
tion.
Word Description Value
0
Configuration information:
• Bit 15: 0 = ATA; 1 = ATAPI
• Bit 7: removable media
• Bit 6: removable controller
• Bit 0: reserved
0C5A
H
1 Number of logical cylinders 16,383
2 ATA-reserved 0000
H
3 Number of logical heads 16
4 Retired 0000
H
5 Retired 0000
H
6 Number of logical sectors per logical track: 63 003F
H
7–9 Retired 0000
H
10–19 Serial number: (20 ASCII characters, 0000
H
= none) ASCII
20 Retired 0000
H
21 Retired 0400
H
22 Obsolete 0000
H
23–26 Firmware revision (8 ASCII character string, padded with
blanks to end of string)
x.xx
27–46 Drive model number: (40 ASCII characters, padded with
blanks to end of string)
ST95005620AS
ST93205620AS
ST92505610AS
47 (Bits 7–0) Maximum sectors per interrupt on Read multiple
and Write multiple (16)
8010
H
48 Reserved 0000
H
49 Standard Standby timer, IORDY supported and may be
disabled
2F00
H
50 ATA-reserved 0000
H
51 PIO data-transfer cycle timing mode 0200
H
52 Retired 0200
H
53 Words 54–58, 64–70 and 88 are valid 0007
H
54 Number of current logical cylinders xxxx
H
55 Number of current logical heads xxxx
H
56 Number of current logical sectors per logical track xxxx
H
57–58 Current capacity in sectors xxxx
H