Service manual

RDM INTERFACE BOARD SCHEMATIC (2 OF 3)
FIGURE3-49
3-60
March 2000
Part No. 001-3139-502
7
P1-6
U125
TP8052AH8640
Y103
11.059 MHz
C108
20pF
C107
20pF
EA
29
30
PSEN
ALE
32
33
34
35
36
37
38
39
PD6
PD5
PD4
PD3
PD2
PD1
PD0
2
P1-1
A0
A1
A2
A3
A4
A5
A6
A7
A15
A14
A13
A12
A11
A10
A9
A821
22
23
24
25
26
27
28
P2-0
P1-2
P1-0
P2-1
P2-2
P2-3
P2-4
P2-6
P2-7
3
1
P3-6
16
P3-7
17
U122D
12
13
5
U112B
6
11
13
D8
15
26
DE
SD
A7
A6
A5
A4
A3
A2
A1
A024
23
22
21
20
19
18
17
Q0
Q1
Q2
Q3
Q4
Q5
Q6
Q7
U123
74HC7030
25
DOR
12
11
10
9
8
7
6
5
D0
D1
D2
D3
D4
D5
D6
D7
D0
D1
D2
D3
D4
D5
D6
D7
MR
DIR
27
3
U105-67 (1)
S1
4
V25 DATA BUS (7:0)
TX FIFO
U122B
6
5
MSTB
4
U6-15 (1)
U105-84 (1)
3
2
1
C
B
A
A13
A14
A15
U128
74HC138
4
5
G2A
G2B
Y2
Y1
14
13
G1
+5V
6
9
8
7
6
5
4
3
2
D8
D7
D6
D5
D4
D3
D2
D1
A0
A1
A2
A3
A4
A5
A6
A7
U126
74HC573
19
18
17
16
15
13
12
11
IO8
IO7
IO6
IO5
IO4
IO3
IO2
IO1
A0
A1
A2
A3
A4
A5
A6
A7
19
18
17
16
15
14
13
12
12
11
10
9
8
7
6
5
D0
D1
D2
D3
D4
D5
D6
D7
D0
D1
D2
D3
D4
D5
D6
D7
Q8
Q7
Q6
Q5
Q4
Q3
Q2
Q1
D0
D1
D2
D3
D4
D5
D6
D7
22
OE
ADDRESS BUS (7:0)
U127
27C256A
EPROM
LOWER ADDRESS LATCH
HSDB
MICROPROCESSOR
ADDRESS
SELECT
A8
A9
A10
A11
A12
A13
26
2
23
21
24
25
A12
A11
A10
A9
A8
A13
20
CE
U122C
10
9
8
U112C
74HC04
98
25
13
26
DE
SD
A7
A6
A5
A4
A3
A2
A1
A0
24
23
22
21
20
19
18
17
Q0
Q1
Q2
Q3
Q4
Q5
Q6
Q7
U124
74HC7030
DOR
12
11
10
9
8
7
6
5
D0
D1
D2
D3
D4
D5
D6
D7
D0
D1
D2
D3
D4
D5
D6
D7
MR
DIR
27
3
15
RX FIFO
SI
4
D8
U105-68 (1)
U122A
74HC32
U112D
12133
1
2
U113-1 (1)
U221
LM78L12ACM
81
2,3,6,7
C271
.001
+
C270
4.7
+12V
SOURCE
U224
LM2940T-5
12
3
C267
.01
+
C266
15
+5V
C113
.01
C114
.01
C115
.01
C117
.01
C121
.01
C122
.01
C123
.01
C124
.01
C125
.01
C126
.01
C127
.01
C128
.01
C288
.01
C289
.01
C290
.01
C291
.01
C292
.01
C293
.01
C117
.01
C118
.01
C119
.01
C120
.01
+
C287
47
+
C129
10
+
C130
10
U223
78S09
11
+9V
SOURCE
C296
.01
C297
.01
+15V
3
OUT
GND
IN
+
C264
15
C298
.01
C299
.01
C300
.01
C281
.01
+
C280
47
C282
.01
C283
.01
C284
.01
C285
.01
C286
.01
C302
.01
C303
.01
C268
.001
+
C269
1.5
C263
.01
+
C295
47
+9V
C265
.01
U201
78L12
31
2
+15V
SOURCE
C260
.01
C261
.01
+15V
F201
2A
+
C262
15
1
U222
MAX735EPA
6
7
C278
.1
+
C277
47
-5V
SOURCE
R294
130k
R295
300k
+
C272
15
C276
.1
+
C275
15
8
2
3
+5V
SHDN
V+
VREF
SS
LX
CR209 L201
5
V OUT
L202
+
C279
47
+
C131
10
U112A
21
27
A14
A14
C EN
OC
11
2
P1-3
4
PD7 P2-5
31
R123
10k
9
RSTU102-5 (1)
U207-8 (3)
LOGIC SQ
U210-14 (3)
RX DATA
8
P1-7
XTAL 1
XTAL 2
19
18