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KX-T7436C/KX-T7436C-B
3. LED CIRCUIT
1) Circuit Operation
The LED executes dynamic lighting for the status indicators, and control is executed by the output ports C0 to C5
(column) and R0 to R9 of IC1.
A fixed pulse (T=1.82 msec) is output continuously from the/SCK1 terminal of IC9. This pulse is counted and the
output of IC1 is shifted sequentially from C0 to C5.
R0 to R7 of IC1 also output pulses, and the lighting of the LED is controlled by the timing of the output ports C0 to C5.
Waveform
3
A
4
D105
CO24
R
G
G
D111
CO18
R
G
G
D104
CO23
R
G
G
D110
CO17
R
G
G
D103
CO22
R
G
G
D109
CO16
R
G
G
D102
CO21
R
G
G
D108
CO15
R
G
G
D101
CO20
R
G
G
D107
CO14
R
G
G
D100
CO19
R
G
G
D106
CO13
R
G
G
D117
CO12
R
G
G
D116
CO11
R
G
G
D115
CO10
R
G
G
D114
CO9
R
G
G
D113
CO8
R
G
G
D112
CO7
R
G
G
D123
CO6
R
G
G
D122
CO5
R
G
G
D121
CO4
R
G
G
D120
CO3
R
G
G
D119
CO2
R
G
G
D118
CO1
R
G
G
D128
AUTO
D127
MUTE
D126
FWO
D125
CONE
D130
ICM
D124
SP
D129
MW
IC1
40
41
38
39
+5V(V1)
L5
R160
C17
J17
L10
C15
R121
R16
R17
R18
R19
R20
R21
R22
R23
R24
R25
L11
R28
R27
C18
C19
Q3
Q4
Q5
Q6
Q7
Q8
Q9
Q10
Q11
Q12
Q13
Q14
Q15
Q16
Q17
D201
LCD
BOARD
BOARD
Q18
C16
R26
+5V(V2)
+5V(V2)
1
31
49
31
49
27
28
29
30
17
35
64
8
28
29
30
17
35
64
8
34
33
50
51
52
53
54
55
56
57
58
59
43
44
45
46
47
48
L12
L13
L14
L15
L16
L17
TXA
TXB
RXA
RXB
VD0
VD0
VD0
VD0
VD0
IP0
IP1
IP2
IP3
IP1
IP2
IP3
GND
GND
GND
GND
GND
CSN
OSO
OSI
R0
R1
R2
R3
R4
R5
R6
R7
R8
R9
C0
C1
C2
C3
C4
C5
22
11
10
10
9
7
6
5
4
3
2
7
6
5
4
3
2
12
63
16
61
62
PI
NI
21
20
19
15
18
20
19
15
18
32
42
60
13
14
42
60
13
14
23
24
25
26
24
25
26
36
37
37
CK2K
INT0
IOR
IOW
A0
A1
D0
D1
D2
D3
INT1
IOR
IOW
A0
A1
D0
D1
D2
D3
INT1
RESET
EP3
SX0
SR1
SR0
EP2
CK2M
SR1
SR0
EP2
CK2M
N.C
N.C
N.C
EP0
EP1
N.C
N.C
EP0
EP1
OP0
OP1
OP2
OP3
OP1
OP2
OP3
CK16M
CK512K
CK512K
+
–
+
–
X1
16.384M
16.384M
Circuit Diagram
A
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