IBM 3274 51C Maintenance Information page 183

Alt IML
Address B 1\ 2 1
0000
II
011......-_ _ _ _ _
\_~
II_L-_~
_ _ _
~Model
51C
Ref
D
D
D
7
This panel is located in the customer access area.
Description
On/Off switch:
III
=
On;
l2J
=
Off.
On indicator: Indicates the 3274 is on.
IML (Initial Machine Load) pushbutton: Pressing
and holding causes a basic test to run. When the
pushbutton is released, 1M L tests start. At com-
pletion, the machine is loaded.
Alt IML Address switch:
• 1: Holding, while pressing the IML pushbutton,
bypasses the tests and loads the machine
directly. Use only after normal 1M L fails.
• 2: Holding, while pressing tho IML pushbutton,
invokes the adapter and wrap test.
Ref
Figure D-3. 3274 Operator Panel - Models 51C/52Cwith 1200-bps Integrated
Modem or External Modem
Description
8 4 2 1 indicators: These light while the IML push-
button is held. During IML, they follow the test
sequence. At completion, they all go out. During
operation, they indicate operational status.
Primary/Secondary Speed Switch -- In the Primary
position the modem operates at normal speed; in the
Secondary position the modem operates at half
speed.
Encrypt/Decrypt Key Switch - Allows a new master
key to be entered when in the horizontal position.
Encrypt/Decrypt Battery - Allows the master key to
be maintained in the 3274 when power is off.
Appendix D. Operator and Control Panels D-5