DISK DRIVE OPERATION

Some parameters are defined as a group of bits. A word which is defined as a set of bits is transmitted with the indicated bits on the respective data bus bit (e.g., bit 15 appears on DD15).

Some parameters are defined as a sixteen-bit value. A word which is defined as a sixteen bit value places the most significant bit of the value on bit DD15 and the least significant bit on bit DD0.

Some parameters are defined as a 32-bit value (e.g., words 57 and 58). Such fields are transferred using two word transfers. The device first transfers the least significant bits, bits 15 through 0 of the value, on bits DD15 through DD0 respectively. After the least significant bits have been transferred, the most significant bits, bits 31 through 16 of the value, are transferred on DD15 through DD0 respectively.

Some parameters are defined as a string of ASCII characters. For the string “Copyright,” the character ‘C’ is the first byte, ‘0’ is the 2nd byte, etc. When such fields are transferred, the order of transmission is:

1st character (‘C’) is on bits DD15 through DD8 of the first word

2nd character (‘o’) is on bits DD7 through DD0 of the first word

3rd character (‘p’) is on bits DD15 through DD8 of the second word

4th character (‘y’) is on bits DD7 through DD0 of the second word, etc.

 

 

 

Table 6-6IDENTIFY DEVICE information

 

 

 

Word

Content

Description

 

 

General configuration bit-significant information:

 

 

15

0=ATA device, set to 0

 

 

14-8

Retired

0

045Ah

7

1=removable media device, set to 0

6

1=not removable controller and/or device, set to 1

 

 

5-3

Retired

 

 

2

Reserved

 

 

1

Retired

 

 

0

Reserved

1

XXXXh

Number of logical cylinders

2

0

Reserved

 

3

00XXh

Number of logical heads

4-5

0

Retired

 

6

003Fh

Number of logical sectors per logical track

7-9

0

Retired

 

10-19

XXXX

Serial number (20 ASCII characters, 0 = not specified)

20

0003h

Controller type(0003h): Dual ported, multiple sector buffer with look-ahead cache

21

03B0h

Buffer size in 512-byte increments (3B0h => 944 => 472KB)

22

0004h

Number of ECC bytes (Device Native length is selected via set feature command.)

23-26

XXXX

Firmware revision (8 ASCII characters)

27-46

XXXX

Model number (40 ASCII characters)

47

8010h

15-8

80h

7-0

Maximum number of sectors that shall be transferred per interrupt on READ/WRITE

 

 

 

MULTIPLE commands

48

0000h

Reserved

 

(continued)

58

SpinPoint V40 Product Manual

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Samsung spinpoint v40, 3.5 hard disk drives manual Word Content Description, Xxxx