Fujitsu MPG3XXXAH-E manual Servo frame format, Scd, Asm Ssm, Pad, Data

4.7.3Servo frame format

As the servo information, the drive uses the two-phase servo generated from the gray code and Pos A to D. This servo information is used for positioning operation of radius direction and position detection of circumstance direction.

The servo frame consists of 5 blocks; write/read recovery, servo mark, gray code, Pos A to D and PAD. Figure 4.6 shows the servo frame format.

0.72 ∝ s	0.16 ∝ s	∝ s	0.17 ∝ s	∝ s	0.74 ∝ s 0.56 ∝ s 0.56 ∝ s 0.56 ∝ s 0.80 ∝ s
	1.81		0.53

PA SCD

ASM SSM

R/W Recovery Field

6.63∝ s

Pos

A

Pos

B

Pos

C

Pos

D

PAD

Servo Frame

DATA

DATA

Servo Frame

86.81∝ s

Figure 4.6 96 servo frames in each track

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