Service manual

7-11
March 2000
Part No. 001-3139-502
VDM SCHEMATIC (1 OF 2)
FIGURE 7-7
FOLDOUT
3
2
1
P1
R118
22k
R117
22k
R119
22k
+5V
4
33
34
35
36
37
38
39
40
CARD
ADDRESS
12
RN1
22k
109876543
U13
74HC573
D7
D6
D5
D4
D3
D2
D1
D0
9
8
7
6
5
4
3
2
LE
11
+5V
1
12
13
14
15
16
17
18
19
Q0
Q1
Q2
Q3
Q4
Q5
Q6
Q7
OC
D8
D7
D6
D5
D4
D3
D2
D1
D0
4
3
2
1
8
7
6
5
R146
22k
R147
22k
R148
22k
R149
22k
+5V
D0
20
D1
D2
D3
D4
D5
D6
D7
D7
D6
D5
D4
D3
D2
D1
D0
19
18
17
16
15
14
13
2
67
68
69
70
MREQ
PT0
PT1
PT2
PT3
MICROPROCESSOR
U7
70320
83
R/W
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
A16
A17
A18
A19
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
A16
A17
A18
A19
U53D
89 66
P17/READY
R153
10k
R152
10k
+5V
R10
10k
R46
10k
Q1
3658
R5
140
U53E
10 11 65
P16/SCKO
R1
10k
R12
10k
Q2
3658
R11
140
Q19
6109
Q20
6109
IDB IDLE 54
IDB IDLE 22
CSB IDLE 56
CSB IDLE 20
CSB DATA 52
CSB DATA 20
IDB DATA 21
IDB DATA 53
U1B/C
3447
+5V
+5V
U53C
U36C
PCM LOOP
U19-7 (2)
MREQ
U49-2/12 (2)
U17-9 (2)
71
72
74
6
73
PT4
PT5
PT7
PO2
PT6
41
RXDO
45
RXDI
5
5
6
6
10
13
9
11
12
15
14
1
2
9
7
15
14
10
11
12
13
6
5
1
2
3
4
15
14
10
11
12
13
6
5
1
2
3
4
9
7
U47A/B
55121
U2A/B
55121
D8
D7
D6
D5
D4
D3
D2
D1
D0
1
2
3
4
5
6
7
8
9
10
11
12
PIGGYBACK
CONNECTOR
J31
U48D
74HC32
U48B
U48A
CS11
CS12
CS13
11
6
3
12
13
4
5
1
2
U53B
U53A
74HC04
44
47
TXDO
TXDI
3
1
4
2
+5V
R85
10k
76
9
49
53
75
VTH
IC
IC
IC
IC
3
43
46
EA
CTS0
CTS1
R68
10k
59
P10/NMI
PO4 PO3 PO6 PO5
8 7 11 10
12
CLKOUT/PO7
12
RTS
21
16
8
18
MC4
DTR
TC
MC1
+5V
IN
11
12
43
44
9
10
41
42
+12V
IN
+12V IN 13
+12V IN 45
TX AUDIO 59
TX AUDIO 60
5
6
7
8
1
2
3
4
U35E
512
R139
0
2
1
S3
R138
100k
R137
100k
J14
R95
300
R94
300
+
C87
10
U34C
+
R103
10k
+4.5V
+
C88
10
R89
10K
C86
.1
TP9
U34D
+
+4.5V
R91
10k
14
9
10
8
13
12
R90
100k
R92
10k
C85
.1
TX FSK
C66 (2)
17
MC0
U16
7911
FSK
TD
MC2
MC3
RC
10
19
20
5
TXDB
26
-12V
IN
-12V IN 14
-12V IN 46
-48V
IN
-48V IN 15
-48V IN 47
RX AUDIO 27
RX AUDIO 28
8
7
6
5
4
3
2
1
U35D
413
R142
100k
2
1
S4
R141
300
R140
300
J15
R99
220k
R97
220k
C83
.1
C81
.1
U34A
3403
+
R100
100k
1
2
3
R98
100k
+4.5V
5
6
7
8
4
3
2
1
S1
J27-2 (2)
J32-11 (2)
U57-8 (2)
PCM FSK
SRXA
J27-3 (2)
C82
.1
R101
10k
U34A
3403
+
+4.5V
R93
10k
7
6
5
TP8
+
C51
2.2
R143
620
R88
10k
R81
10k
+5V
+5V
U33B
U33D
U33C
6
8
9
1110
12
3
5
4
R33
10k
Q18 (2)
FSK LOOP
+5V
15
30
31
29
OP7
TXDA
RXDA
OP0
RXDB
11
10
14
Y2
2.46 MHz
C59
20pF
C58
10pF
23
24
RD
XTAL2
XTAL/CLK
R104
910
C89
.0022
8
7
CAP1
CAP2
+5V
11
1
BRTS
RING
3
RESET
U36F
1213 34
RESET
R22
10k
7
IP0
Y3
3.69 MHz
C4
10pF
C6
5.1pF
32
33
X1/CLK
X2
A3
A2
A1
A0
6
5
3
1
R23
10k
+5V
21
36
RS4
RS3
RS2
RS1
CS
IP2
IRQ
IP3 IP6
R32
10k
1
237
IP1
4
R28
10k
+5V
38
39
9
8
IP5
IP4
R
W
U6
2681
DUART
OP1
D7
D6
D5
D4
D3
D2
D1
D0
25
16
24
17
23
18
22
19
12
D7
D6
D5
D4
D3
D2
D1
D0
OP2
OP3
OP4
OP5
OP6
28
13
27
14
26
U35C
3
15
2
U35B
26 RXDB
25 TXDB
P1
R67
10k
R19
10k
R82
10k
R21
10k
R29
10k
R166
10k
+5V
U46D
U46E
U46C
U46F
U46A
U46B
74C906
89
11
5
13
1
3
10
6
12
2
4
RN2
10k
+9V
2
3
1
45
678
U31-6 (2) FSR
U31-5 (2) TX PCM
U31-13 (2) TX DTMF
U30-5 (2) RCM
U30-13 (2) PCM LOOP
U31-12 (2) AUDIO
AUDIO
CONTROL
LINES
62
61
58
57
56
55
54
52
51
48
81 FSK RESET
P13/INTP2
P12/INTP1
P27/HLDRQ
P26/HLDAK
P25/TCI
P24/DMAAK1
P23/FMARQ1
P22/TC0
P21/DMAAK0
P20/DMARQ0
RESET
U25-13 (2) TX PSC
U21-13 (2) TXPCC
U19-18 (2) PCM M-LEAD
U23-6 (2)
U22-3 (2)
U22-4 (2)
U22-5 (2)
U22-6 (2)
U29-5 (2)
U19-8 (2) PCM E-LEAD
TX PCM
SLOT
ADDRESS
Y1
10 MHz
C17
10pF
C15
10pF
78
79
X1
X2
P11/INTP0
60
5
6
3
2
7
RST
RST
SENSE RESIN
CT
REF
C11
.1
+
C10
2.2
R154
10k
R150
10k
S2
RESET
+5V
35
R109
10k
+5V
U58B
5
4
6
U12
74HC154
A16
A17
A18
A19
23
22
21
20
A3
A2
A1
A0
4
11
CS3 U49-13 (2)
CS10 U49-10 (2) Y10
Y3
2
13
14
15
CS1
CS11
CS12
CS13
Y1
Y11
Y12
Y13
ADDRESS
DECODER
U50-1 (2) CS4
U17-10 (2) CS5
U49-1 (2) CS9
5
6
10
Y4
Y5
Y9
19
18
CS1 CS2
Y0
Y15
171
3
Y2
CS2
2
1
3
+5V
J24
1
Vpp
27
A14
A14
A15
A13
A12
A11
A10
A9
A8
A7
26
2
23
21
24
25
A13
A12
A11
A10
A9
A8
A7
A6
A5
A4
A3
A2
A6
A5
A4
A3
A2
3
4
5
6
7
8
U10
27C256
A1
A1 9
A0
10A0
CE
20
EPROM
A11
A10
A9
A8
A7
23
21
24
25
A11
A10
A9
A8
A7
A6
A5
A4
A3
A2
A6
A5
A4
A3
A2
3
4
5
6
7
8
A1
A1 9
A0
10A0
A12 2
A12
22
OE
22
OE
11
12
13
15
16
17
18
19 D7
D6
D5
D4
D3
D2
D1
D0
O0
O1
O2
O3
O4
O5
O6
O7
11
12
13
15
16
17
18
19 D7
D6
D5
D4
D3
D2
D1
D0
I/O1
I/O2
I/O3
I/O4
I/O5
I/O6
I/O7
I/O8
20
CS1
+5V
19
CS2
WE
27
U58D
12
13
11
U58A
3
12
1
2
13
R112
47k
R113
47k
Q16
3658
R116
47k
R107
10k
R114
910
R115
1k
-5V +5V
+5V
Q15
3658
+5V
R152
10k
R111
10k
Q14
3658
CR404
(GREEN)
POWER LED
R108
10k
R110
22k
+5V
1
2
3
4
+5V
IN
Z3
1
2
3
+
C101
47
C100
.01
CR11
6.2V
+5V
SOURCE
+12V
IN
Z1
1
2
3
+
C90
47
C92
.01
+12V
SOURCE
12
3
4
U42
78S09
+
C91
47
C93
.01
R105
1k
R106
1k
+9V
SOURCE
+
C95
10
C94
.01
+4.5V
SOURCE
5
Z1
2
3
+
C90
47
C92
.01
-12V
SOURCE
12
3
4
U42
78S09
+
C91
47
C93
.01
+9V
SOURCE
8
7
+12V
IN
6
F1
1A
F2
.5
F3
3A
P2
8
7
NOTES:
1. ALL RESISTORS ARE IN OHMS AND CAPACITORS IN MICROFARADS
UNLESS OTHERWISE SPECIFIED.
2. IC PIN NUMBERS NOT SHOWN:
U1, U2, U47
U3, U17, U46, U48
U6
U7
U10, U11
U12
U13
U15
U16
U34
U35
IC
+5V
-5V +9V
GND
PIN NUMBER
16
14
40
50/80
28
24
20
8
2
16
4
8
4
1
8
7
20
42/77
14
12
10
4
9/22
11
9
+9V
C28
.01
C30
.01
C31
.01
C32
.01
C34
.01
C38
.01
+5V
C1
.01
C2
.01
C7
.01
C8
.01
C9
.01
C12
.01
C13
.01
C14
.01
C16
.01
C18
.01
C19
.01
C20
.01
C21
.01
C22
.01
C23
.01
C3
.01
C24
.01
C25
.01
C26
.01
C27
.01
C33
.01
C35
.01
C36
.01
C37
.01
C41
.01
C45
.01
C46
.01
C47
.01
C48
.01
C49
.01
C99
.01
RAM
SECONDARY AUDIO TX
SECONDARY AUDIO RX
FLASH
EPROM
S5