IBM 5280 Manual page 98

V
6
DATA ENTRY MAP
A-El DISPLAY
PAGE 8 OF 10
044
Probe
A-E3D02~
'1 MHz Clock'
(MIM 531).
Up light: On
Down light: On
Are the lights correct?
Y N
045
For the line probed in the
previous step,
Up light: Off
Down 1 i ght: On
Are the lights correct?
Y N
046
Failing Diskette/Main MPU
Card (A-Cl) (MIM 303).
- If a 'ROS Patch' cable is
connected to the card,
GO TO MAP 0600,
ENTRY POINT A.
047
The '1 MHz Clock' line is
failing. Suspect a shorted
net. Use the net list (MIM
531) to isolate the problem.
OR - - - - -,
Failing Diskette/Main MPU
Card (A-Cl) (MIM 303).
- If a 'ROS Patch' cable is
connected to the card,
GO TO MAP 0600, ENTRY POINT A.
y
MAP 1011-8
048
Power off.
Remove the
terminating
resistor.
- Set the CE meter to the RXI
scale.
Disconnect POI on A-El (MIM
201, 203, 227).
Connect the positive end ~f the
met e r
t
0
A- E 1- P 0 1- 4 , ,
+
V ; de
0
Drive', and the negative lead
to ground (MIM 201, 203, 227).
The meter should read in the
range of 30 ohms to 150 ohms.
Is the meter reading correct?
Y N
049
- Use MIM 227 to trace the '+
Video Drive' line for opens
or grounds.
- OR - -
- GO TO THE 5281 OR 5282 DATA
STATION DATA ENTRY MAP 1000,
ENTRY POINT A.
050
- Failing Data Station Adapter
Car d (A- E
I) (
M 1M 501).
EC840874 PEC839787
Y MAP 1011-8