HP 7942 Service Manual page 105

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NOTES:
I. BOXED NUMBERS BINDICATE
NIRE COLOR CODE AS FOLLONS:
COLOR
A
B C
BLAt K 0 0 0
BRONN I 1 1
RED 2 2 2
ORANGE 3 3 3
YELLOW 4 4 4
GREEN 5 5 5
BLUE
6 6 6
VIOLET 7 7 7
GRAY B B B
WHITE 9 9 9
FlLE=FSJEf03B
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2 r---t-+----i
: 7
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10 : B
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! ! : 9 KEY
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13 III
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15 : 13
t5V
SND
PVAL-H
t
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FAN
B 1
TO DOC
PCA-A2
(f R A 21
...
HOST
COMPUTER
t5V
GNO
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HOST DEPENDENT
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CON T R 0 L L E R
J2
PCA-A5 ( F R A 5 )
! 3
14
16
17
1 B
20
2 !
22
J3 23
0101 - L 25
DI02-L 26
OI03-L 27
DI04-L
2 B
EOI-L 30
o
AV - L 3 I
NRFD-L 32
NDAC-L 33
IF C - L 35
SRQ-L 36
AT N - L 37
OI05-L 3 B
DI06-L 40
DI07-L 4 I
OIOB-L 42
REN-L 43
12,IB-24 SND 45
46
4B
49
3,5,7,10.12,15.
19,24,29,34
WIP2 J4
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DATA/CONTROL
INTERFACE BUS
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N2PI
W2
MPO-L
PVAl-H
CSRS-L
CSWS-L
CSAQ-H
CSAt-H
CSA2-H
CSA3-H
CSA4-H
SEL-L
CSA5-H
CSBO-H
CSBI-H
CSB2-H
CSB3-H
CSB4-H
CSBS-H
CSB6-H
CSB7-H
DATAO-H
OATAI-H
DATA2-H
DATA3-H
OATA4-H
OATA5-H
OATA6-H
DATA7-H
ORIN-L
OROUT-L
OSIN-L
OSOUT-L
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ST-506
INTERFACE
HS8-L
HS4-L
WGATE-L
SKCMP-L
TAKO-L
HL T-L
HSO-L
HS2-L
iNUX-L
ROY-L
STEP-L
OS 0 - L
01 R - L
GNO
WMFMt
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RED
t 5 V
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SREEN-L
G R EE N
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t I 2 V
GNO
GNO
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GND
N3P3
Service Information
7942 and 7946
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DIS
CDR
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ASSEMBLY Ai
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Figure 4-12. Disc Signal Distribution
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