Table of Contents
Advertisement
a) Track jump counter
Whentracks are consecutively crossed, a tracking error
signal will not fail to cross the DC offset point in both on-
and off-track modes as shown in Fig. 40. This point,
threrfore, is used to determine either on- or off-track so
as to count the number of cycles in which the on-track is
switched over to the off-track. A count value is set by
the microcomputer.
And this count value is given
priority to the kick-setting time.
Aa ee a
|
|
|
|
|
RF Signal
( MIRR )
TECO or TEC1
z
Input Signal
TEC Comparator
:
|
4
1
{
1
1
'
1
i
1
a
Pied
i dtd
do
O
\
O
|
O
|
O
|
OQ ——
Avalue of MIRR at TZD edge
0: ON Track
1: OFF Track
The number or cycles in which 0 changes to 1 should be counted.
Track count jump
Fig. 40
3. CLV Control Stage
(1) CLV control command
and CLV mode command
MSB
LSB
Fae ae)
| 0 | RFCK/4 and WFCK/4_
| Select a steady servo phase
| 1 | RFCK/8 and WFCK/8 | comparison signal.
G2
RFCK/16
Select a bottom hold cycle of
Control Status
RFCK/32
pull-in and rough servos.
MOF, MOR (H, Z) outputs | Select an MDF/MDR output
MDE, MDR ({H, L) outputs | terminal selecting method.
L
| MOR
| LH |
G fof
1208
Select the gain of pull-in and
[vas on se
T | 0 |
RFCK/2
Select a peak hold cycle of
1
RFCK/4
pull-in servo.
79
Advertisement
Table of Contents
