IBM SY27-0345-06, Service And Maintenance Manual

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MAP 0190: Service Terminal Display Unreadable
Symptom Explanation Conditions That Could Cause This Symptom
While you are diagnosing a
problem, a terminal attached to the
service port of the 2210 displays
random characters instead of read-
able text.
Ÿ
Incorrect configuration setting of the terminal or 2210
service port.
Ÿ
Incorrect terminal/device (ac) grounds.
Ÿ
Defective, incorrectly shielded, or incorrectly grounded RS
EIA 232 cable between the terminal and the 2210.
Ÿ
Defective terminal or terminal emulator.
Ÿ
High ambient electromagnetic interference (EMI) levels.
Ÿ
Power line disturbances.
Ÿ
Defective 2210 system board.
001
Does the IBM 2210 go to the active state within 2 minutes of resetting or pow-
ering on?
Active state is indicated by the green system LED on and the amber system
LED off.
Yes No
002
Go to Step 004
003
Go to Step 007 on page 2-18
004
Is the bootstrap monitor active with the green system LED on and the amber
system LED blinking?
Yes No
005
Go to “MAP 0100: Start” on page 2-2.
006
The bootstrap monitor cannot find a boot path. You must correct the boot problem
before you can correct the display problem
– Press the service terminal break key sequence and press Enter.
A typical terminal break key sequence for PC terminal emulators is Alt-b. Most
ASCII terminals have a Break key (often used in conjunction with the Ctrl key).
(Step 006 continues)
Chapter 2. Problem Determination
2-17