IBM 3590 - Manual (Page 84)

– Random mode must be selected from the SET ACF MODE menu.
v Enabling conditions: Random mode is enabled if all the following
conditions are met:
– The magazine is installed in the ACF.
– The magazine lock is in the locked state.
– A valid Move Medium command is received.
v Disabling conditions: The ACF is disabled in Random mode if one of the
following conditions are met:
– The magazine is removed from the ACF.
– The magazine is unlocked.
– An attention condition is detected in the ACF; for example, extra
cartridge condition.
v Operation:
1. When first enabled in Random mode, the ACF waits for attaching host
commands.
2. All magazine cell-status indicator LEDs are set to in-use (steady green).
The in-use indicator LEDs remain on unless Random mode is disabled.
The priority cell cell-status indicator LED is activated as it is used.
3. All cartridge movement is under control of the attaching host by using
the Medium Mover commands.
4. The ACF honors the Prevent Allow Media Removal command. It does
not allow operator-initiated export of cartridges any time the command
has specified Prevent Media Removal.
5. The priority cell has an assigned element address and can be accessed
by the accessor under attaching host control. If an operator inserts a
cartridge in the priority cell, the ACF notifies the attaching host. The
ACF will not access the cartridge in the priority cell unless commanded
by the attaching host.
6. If a cartridge that was loaded while in Random mode is unloaded, it
may not always be returned to its cell of origin. The attaching host
controls the cartridge location. When the cartridge is placed in a
magazine cell, it is placed in the import position.
Cell Status Indicator LEDs
This section describes the operation of the cell status indicator LEDs for the
ACF and the priority cell. It also describes the conditions that are identified
by the indicator LEDs. The indicator LED operations are described under the
following headings:
v “Cell Status: Flashing Yellow–Attention indicator LED” on page 65.
v “Cell Status: Steady Yellow–Alert Conditions” on page 66.
64 3590 Operator Guide