N
Y
N
N
N
N
N
Y
CD switched on
(mode switch)
+A(CD)
supplied to
CD part?
Decoder delivers CLOCK -
frequ. 4.23MHz to µP.
µP-
RESET
line → high
µP init. Decoder 7801.
inner switch
closed?
4s time-out over?
0,2s time-out over?
inner switch open?
Laser on
Disc motor 100ms on
FOCUS search
on
focus found? 3s time-out over?
N
startup proc.
stopped,
display shows
µP initializes Decoder
and Servo IC:
-start turntable
-adj. track bal. and gain
-read subcode (TOC)
TOC
found?
display shows
max. trackno.
Y
Y
Y Y
N
Y Y
Remark: To check focus servo, slide servo, track servo and turntable
use service test program
- Battery empty?
- check +A,
- mode switch o.k.?
check: - Motor control pin 27 of Decoder 7801 and
Disc Motor driver 7805
- HF Signal by using service testprogram
check: - Laser light on ?
Check pin 38 of 7803 and
LASER CONTROL
circuit
- Focus Servo
HIGHLOW
Level on
pin23
(CD-RESET)
after 100µs?
Init. 7801 for ext. DAC Init. 7801 for int. DAC
BEGIN
µP moves slide inside
(4s time-out starts)
µP moves slide outside
(0,2s time-out starts)
STOP MODE STARTUP FAILED
CDstartup EVA, 080997
slide off
N
Y
check: - door switch
Door closed?
Display shows
check: - +A(CD), +B(CD), +LASER, +M,
- time constant of reset circuit
- Pin 32 of µP 7800 HIGH ?
- Pin 30 of µP 7800, if 4.23 MHz o.k.
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