IBM 5280 Manual page 103

B
DATA ENTRY MAP
2
A-Al KEYBOARD
PAGE
3
OF 11
002
Note: The System must be
dedicated to maintenance at
this time.
- Power off.
- Ensure that all Diskette
locking levers are open.
Power on.
Wait at least 30 seconds for
the condition code table to be
displayed on Data Station 0
(t-lIM 931).
Is there a Scan code for Keyboard
o
displayed in line 1 of the
condition code tables (MIM 93l)?
Y N
1
003
(ENTRY POINT B)
- Probe the '100 Hz Clock' line
at A-A4B02 (MIM 531).
Up light: On
Down light: On
Are the lights correct?
Y N
004
For the line probed in the
previous step:
Up light: Off
Down light: On
Are the lights correct?
Y N
I 4
C D E F
E F
MAP 1020-3
005
Defective 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.
006
Power off.
Set the CE meter to the RXl
scale.
- Connect the positve lead to
A-A4B02, '100 Hz Clock', and
the negative lead to ground.
Is the meter reading 30 ohms or
above?
Y N
007
- Leave the meter connected as
in the previous step.
Use the net list (MIM 531).
Remove each card in the net,
one at a time, until the
meter reads 30 ohms or above.
Replace the last card
removed.
- If all the cards in the net
have been removed and the
meter reading is still below
30 ohms, suspect a ground on
the Logic board.
008
Defective 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.
EC840874 PEC839787
MAP 1020-3