HP 4262A - Page 254

A25 Board Diagnostic Flow Diagram
Under Fold
Register Output
Bu Rack?
i. Remove AlL,AI2,A1Y
M START /™ A2IPA9
START ——> 0 M4 boasts fron STOP \_AZSPAS
CLOCE_/~ ARTF2
the
Sorvice Kit to cbserve
SIowniRE
Check A25UL3
3. Set Suitech A21S1 to o
1IP-18 positicn.
4.
Discomvect
HP-I3
cable
Window
Test
YYES
_/
Is
Sigoatore
Set
46
YES
1s
Signatare
Sat
ST\NO
Signatures
st
A25\vEs
from
WPo18
connactor
W5V
23HC?
ok?
toze
Bat
53
U7
pin
8
and
US
hock
A
A,
‘pin
4
OK?
and
U1,
5. Set iastrwmcnt addre
000
into
ADDRESS
Mo
ad
E
o
switch
A3SL.
.
.
Go to Figore 8-19, @
Flow
Diagram
B.
Sock
Node?
JES
m);r
{:;:;fl
Ia
Stguaturs
c‘““’
YES
::
s
Sigaatare
of
YHO
§‘S.§{‘
4,:'",2’"
Tptn
&
CF8T?
Flow
Is
Sigusture
at
A23YNQ
Suck
Node?
YO
Check
AISUS,
CLOCK
./~
A22TP2
T
p
:,,mm
olf
and
<5V
72477
Diagram
E.
[
Momentarily
ahart
Momentarily
short
7]
ctrouit
A25U4
pin
&
cireuit
AZ5U¢
in
9|
=
=
to
etrcult
common,
to
circuit
common.
'
Check
A25018
.
and
U13.
A
iow
Is
Sigrature
ot
Go
1o
Plgure
8-19,
Troslastoot
X
A250T
un
11
OK?
Fiow
Diagram
B.
a
3
-
NO -
i
1a
Sighature
Set
47)EES
12
Stgnature
al
A25\YED
YES
Buck
Node?
JIE5.4
Troubleshoat
Nanoprocessor
Suck
Nods.
OK?
Ut
pin
8
TAII?
Dats
Bus
Stuck?
K
o
N
so
o
H
Data B M
s
.
Duv/Rec
Outpt
JEEZ
Troubleshoot
Stuck
Node?
JLES
Troubleshoot
Registar
Outpet
YES.
“Prodhleshoot
Chack
AZSUI4,
Chack
A25U7.
Pus
Stuck?
Stuck
Bus.
stack
Node,
Bus
Suck?
Stuck
Bus.
1S,
w6,
U1d,
118204 G18.
[NO [Ne ko
Check
AZ5U2
Check
AZ5US.
@
and U3,
y
{
Troubleshoot
Check
AZ5UL0
:
Stnck
Bus.
aud
U
AE 4 Comparator Control
SERVICE SHEET 24
887
see msior
Figure 8-65. A25 HP-IB Interface Board Diagnostic Flow Diagram.