Servo frame
(126 servo frames per revolution)
|
|
|
|
|
| IGB |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| OGB |
|
| |
|
|
|
|
|
|
|
|
|
| Data area |
|
|
|
|
|
|
| ||||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
|
| expand |
|
|
|
|
|
|
|
|
| |||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| ||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |||||
|
| CY1 n + 1 |
|
| CY1 n |
|
|
|
|
|
| CY1 n – 1 |
|
|
| (n: odd number) | |||||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| ||||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |||||||||
|
| W/R Recovery | W/R Recovery |
| W/R Recovery |
|
|
|
| ||||||||||||||||
|
| Servo Mark |
| Servo Mark |
|
|
|
| Servo Mark |
|
|
|
| ||||||||||||
|
| Gray Code |
| Gray Code |
|
|
|
| Gray Code |
|
|
| Diameter direction | ||||||||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |||||||
| Erase |
| Servo A |
| Erase |
| Servo A | Erase |
|
|
|
| |||||||||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| ||||||||
| Servo B |
| Erase | Servo B |
| Erase | Servo B |
|
|
|
| ||||||||||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Circumference direction |
|
| Servo C |
| Erase | Servo C |
|
|
| Erase |
|
|
|
|
| |||||||||||
|
|
|
|
|
|
|
|
|
| ||||||||||||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
| Erase: DC erase area | |||||||||||
|
| Erase |
|
| Servo D |
| Erase |
| Servo D |
|
|
|
| ||||||||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |||
|
|
|
|
|
|
|
|
| PAD |
|
|
|
|
|
|
|
|
|
|
|
|
| |||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Figure 4.5 Physical sector servo configuration on disk surface
(2)Servo burst capture circuit
The four servo signals can be synchronously detected by the STROB signal,
(3)A/D converter (ADC)
The A/D converter (ADC) receives the servo signals are integrated, converts them to digital, and transfers the digital signal to the DSP unit.
4 - 14 |
|
