Kenwood TK-250 Service Manual page 26

TK-250
SEMICONDUCTOR DATA
Display microprocessor: 75308BGK739BE9 (IC451)
• Pin connection
812
813
814
815
816
817
818
819
820
821
822
823
824/BPO
825/BP1
826
827
828
829
830
831/BP7
~o
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
75308BGK739BE9
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
P60/KRO
o
X2
o
X1
o
NC
o XT2
o XT1
o
VOD
P33
P32
P31/8YNC
P30/LCDCL
P23/BUZ
P22/PCL
P21
P20/PTOO
o P13/T10
o P12/1NT2
o P11/1NT1
o P10/iNTO
P03
• Pin function
26
Pin No.
Pin Name
1/0 Function
Pin No. Pin Name
1/0
Function
812-831
0
LCD output (820-80).
46-49 P20- P23
-
Open (not used).
COMO
0
LCD COMO. 50 P30
0
8erial (RX) data output.
COM1
0
LCD COM1.
51,52 P31,32
-
Open (not used).
COM2
0
LCD COM2. 53 P33
0
LAMP LED output.
COM3
0
LCD COM3. 54 VDD
-
+5V. BIA8
0
LCD power supply voltage.
55 XT1
-
+5V.
VLCO- VLC2
-
LCD voltage level generator.
56
XT2
-
Open (not used).
P40-P43
-
Open (not used).
57 NC
-
Open (not used).
Vss
-
GND.
58,59
X1,X2 I
8ystem clock input
P50
0
GREEN LED output
60
P60
I
GND. P51
0
RED LED output
61 P61
0
Reset output
P52,P53
-
Open (not used).
62,63 P62, 63
-
Open (not used).
POO-P02 I GND. 64 P70
1
LO switch input
P03
I
Rotary encoder input
65
P71 I
TA switch input
P10
1
Rotary encoder input.
66
P72
I
D/A switch input.
P11
1
8erial (TX) data input.
67 P73 I
8CN switch input.
P12 I
GND.
68
RE8ET I
Power on reset input.
P13
0
Test output.
69-80
80-811
-
Open (not used).