IBM System/370 Operator's Reference Manual page 185

IBM 3340 Disk Drive (cont'd)
Disable Read Only Function
1. With the data module removed from the drive, return the IBM logo inset to
its origina,l position (reverse 180°)
(e).
2. The data module may now
be
loaded into the desired drive.
Note: Do not attempt to enable or disable the Read Only function while the
data module rests in the drive shroud recess.
Operating Hints
When you take a 3340 drive offline and want to start it up again, press START STOP. The
drive cycles up. Then press the ATIENTION button. ATIENTION must be used to signal
the system that the drive is ready.
Do not use Power-On or Power-Off switches to load or unload the data module, because
these switches are bypassed by the subsystem sequencing controls during a subsystem
power-up or power-down operation. Power is turned on or removed by the subsystem
sequencing controls.
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