User Data Being Changed (Micro Board Failure) - Tatung OMNISCAN SERIES Service Manual

6.29 USER DATA BEING CHANGED (MICRO BOARD FAILURE)
ie : .. If have any problem on the ID1, ID2, H. POLARITY or V. POLARITY circuit, the microprocessor will take
the different input signals as the same signal and give tHem the same memory address. So the original
data which is written before will be changed at the second-time writing.
I
I
ID1 DETECTION CKT.
I
I
L
NG
NG
r----------------------------
I
ID2 DETECTION CKT.
I
I
L---
I
I
H. POLARITY
DETECTI01 CKT.
1
L--
I
I
V. POLARITY
DETECTION CKT.
I
1
L
NG
USER DATA
BEING CHANGED
I
I
I . .
CHECK ID1 -'--_. _.
-------->
0557,
C561, D508
I. . ...
D509, R582, C560
I
I
OK
I
1
I
>1
I
1
1
CHECK 102 ------------------) R587, C558,
0515
1
1
I
OK
I
I
I
>1
1
I
1
H. POLARITY
---------------->
0555, 0554, R574
CORRECT C556, D505, R573
I
,
I
OK
,
I
>'
1
I
I
1
V. POLARITY
------------->
0558, 0559, R575
CORRECT C557, R585
I
I
I
I
I
>1
1
END
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