36
SC-27
1
2
3
4
A
B
C
D
E
F
1
2
3
4
Step 3: EXTAL Clock
Check the o
u
tp
u
t of pin 4 of IC2601
(Port Expander) on the path.
X2501 (Pin 1)
24ON
X2501 (Pin 3)
Is the logic
gate "H"?
No
Yes
S
T
Does the
crystal oscillate
at 24.576 MHz
?
No
Yes
Check the path, or replace IC2502.
Replace X2501.
Check the path.
IC2502 (Pins 3,8)
BUFFER
No
Yes
U
IC2301 (Pin 80)
1stDSP EXTAL
No
Yes
V
To Step 4
Is there
a clock o
u
tp
u
t
(24.576 MHz)
?
Is there
a clock inp
u
t
(24.576 MHz)
?
Check the path.
IC2401 (Pin 45)
2ndDSP EXTAL
No
Yes
W
Is there
a clock inp
u
t
(24.576 MHz)
?
Step 4: Audio Si
g
nal
Check the signal path.
Check the signal path.
Check the signal path.
Check the signal path.
Check the signal path.
IC2301 (Pins 89,134) MCLK
BCK
LRCK
No
Yes
X
IC2401 (Pin 73)
No
Yes
Y
IC2301 (Pin 94)
No
a
IC2301 (Pin 97)
b
IC2301 (Pin 93)
DATA
No
Yes
Yes
No
Yes
Z
To Step 5
Are there
MCLK inp
u
ts to
1st DSP
?
Is there a
MCLK inp
u
t to
2nd DSP
?
Is there a
BCK inp
u
t to
1st DSP
?
Is there a
LRCK inp
u
t to
1st DSP
?
Is there a
DATA inp
u
t to
1st DSP
?
