IBM B-Series, Maintenance Information

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6
Security Key Lock
The security key lock locks the door closed. The Security Key lock on the library helps maintain
security for cartridges in the library unit. It is a physical lock only, and is not sensed or controlled by
the initiator or device. When locked, the only way to add or remove cartridges to or from the library
units is through the priority cell.
7
Magazine 2 In Use Indicator
The yellow LED indicates the status of Magazine 2. When it is on, the operator should not add or
remove cartridges to or from that magazine and should not remove that magazine from the library unit.
The Magazine In Use LED is on when a cartridge from the magazine has been transported to the
drive for processing, or when the library unit is in random mode and the initiator has issued the
Prevent/Allow Medium Removal command with the prevent bit set.
The LED also turns ON solid momentarily during power-on reset as a lamp test, and it flashes during
bring-up diagnostics.
8
Magazine 1 In Use Indicator
This yellow LED indicates the status of Magazine 1 and operates the same as indicator
7
.
9
Priority Cell In Use Indicator
This yellow LED indicates the status of the priority cell. When the LED is on, a cartridge is in the
priority cell or the priority cell is reserved for the cartridge currently being processed in the drive. When
the LED is on, the operator should not place a cartridge in the priority cell or remove a cartridge from
the priority cell. When the LED is not on, the operator can place a cartridge in the priority cell for
processing or can remove a cartridge from the priority cell. The indicator is visible with the door open
or closed.
This LED turns ON solid momentarily during the power-on reset as a lamp test, and flashes during the
power-on diagnostics. After completion of the power-on sequence, this LED is turned OFF until it is
turned ON by activity that involves the priority cell.
1
Power On/Off Switch
This switch is connected to the dc power supply by a cable. The switch removes dc power from the
output of the power supply. There is no LED to indicate a power-on condition of the library units. The
power is on when the operator panel is active.
Note: With the switch in the Off position, ac voltage is still available inside the subsystem power
supply.
11
Scroll Up Button
12
Scroll Down Button
13
Enter Button
14
Serial number (above lever opening)
Subsystem Initialization
Subsystem initialization includes power sequencing, initial microprogram load (IML), and subsystem
diagnostics.
Initial Microprogram Load:
During an initial microprogram load (IML), a microcode image that
permits the subsystem to become functional is loaded into the subsystem RAM.
When the subsystem is powered on, the unit attempts to perform an IML from flash EPROMS.
INTRO-46
IBM 3570 MI