M2488 PRODUCT GUIDE MEDIA CHANGE R COMMANDS
March 1997 CG00000-011503 REV. A 6- 33
** NOTE **
Since the Mode can also be set via the Medium C hanger operator
panel, the actual mode of operation (and the Mode reporte d via t he
MODE SENSE command) will be the current Mode. The current
Mode is the most recent Mode set by either a MODE SELECT com-
mand from the initiator, or a Mode change reported by the Medium
Changer (operator panel).
Table 6-37. Page Code 00 - Device Unique Parameters Field Description
BYTE BIT VALUE DESCRIPTION
2 0-1 The Mode Code field allows the host to configure the Medium Changer to operate
in one of three operating modes. In the Manual Mode, a single cartridge may be
inserted manually into the tape unit and removed in conjunction with the operator
panel keys. This mode is not selectable by the MODE SELECT command. When in
Manual Mode, the Load/Unload and Move Medium commands can be used to
unload a cartridge. In the Auto Mode, when a cartridge is unloaded, the next car-
tridge is automatically loaded. In the System Mode, the host system is responsible
for cartridge movement activity through the use of Medium Changer commands.
The Mode Code is reported as changeable on a MODE SENSE command. The
default value is 01b (Auto Mode). Modes codes are defined in Table 6-38.
2 2-3 The Eject Code is reserved and not changeable for an FACL, and will result in a
CHECK CONDITION status if not set to 00b. For an ACL, the Eject Codes are
specified in Table 6-39.
2 4
0
1
The purpose of the HltLd bit is to facilitate Dynamic Device Reconfiguration
(DDR). This function allows the host software to suspend the automatic loading of a
cartridge until the operator can move the selected cartridge to another MTU. This bit
is reported as changeable on a MODE SENSE command. The default value is zero.
If the HltLd (Halt Load) bit is set to 1, the Medium Changer is instructed to suspend
loading of the next cartridge following an unload of the currently loaded cartridge
when the Medium Changer is set in Automatic Mode.
3 The Position field describes the current location of the elevator with respect to the
magazine. A value of 00h indicates that the magazine is not loaded. A value of 01h
indicates the magazine position 1 is located at the Tape Load Port. This field is
reported as NOT changeable on a MODE SENSE command.
For an FACL, the Position field is unused, i.e. contains 00h. This field is reported as
NOT changeable on a MODE SENSE command.
4-7 The Cartridge Map field is returned in Mode Sense data to indicate which positions
in the magazine contain units of media (cartridges). A one indicates a cartridge is
present in that position. A zero indicates a cartridge is not present in that position.
The Magazine Present bit in the Cartridge Map field indicates whether or not a mag-
azine is present (1 indicates presence of magazine). P1 refers to magazine slot 1
which is the first slot in the magazine, located at the topmost position of the maga-
zine. The Cartridge Map field is reported as NOT changeable on a MODE SENSE
command. The cartridge map bits are shown in Table6-41.