LG SB74 Service Manual page 22

5. CD STOP ACTION SLE+/SP+/T+/F+ WAVEFORM
U704 pin21
U704 pin20
U704 pin4
U704 pin2
6. CD READING CD-MCK/DIN/RW/BUSY WAVEFORM
U703 pin41
U703 pin19
U703 pin20
U703 pin21
14
Sp+
15
SLE+
16
TE+
17
FE+
18
MCK
19
DIN
20
RW
21
BUSY
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