The green and amber LEDs are status indicators for the EXB-8500. The green LED indicates that the EXB-8500 can accept a tape access command, while the amber LED indicates SCSI bus activity and EXB-8500 error conditions.
Figure 3-1 EXB-8500 Front Panel
Table 3-5 describes the EXB-8500 states indicated by the LEDs.
● The LED is on.
❍ The LED is off.
❊ The LED is flashing, as follows:
– A slow flash is about one flash per second (0.94 Hz) – A fast flash is about four flashes per second (3.76 Hz).
When the
The EXB-8500 state is... Take this corrective action...
● ● Power-on initializationa none
❍ ❍ Passed power-on self-testb
none
● Ready and tape loaded
●or❍c slow❊ Normal tape motion
none fast❊ High speed search/rewind
●or❍or
❊
four❊s
then❍ Servo error
Reset the EXB-8500 by pressing the unload button. If this does not clear the error, power the EXB-8500 off and back on again. If the error occurs again, the EXB-8500 needs service.
slow❊ ●or❍
CRC faild
Power the EXB-8500 off and back on again. If the error occurs again, try reloading new code. If the error persists, the EXB-8500 needs service.
Unrecoverable faultd
Reset the EXB-8500 by pressing the unload button. If this does not clear the error, power the EXB-8500 off and back on again. If the error occurs again, the EXB-8500 needs service.
fast❊
❍ Failed power-on self-test Power the EXB-8500 off and back on again. If the error occurs again, the EXB-8500 needs service.
●or❍ Unload button fail
a The EXB-8500 is performing power-on self-test diagnostics. This takes less than 60 seconds.
b The green LED may go off before the amber LED if no tape is loaded.
c The amber LED is on (●) when data transfer is occurring on the SCSI bus. The amber LED is off (❍) when no data transfer is occurring. The combination of on and off may appear as an irregular flash.
d CRC failures occur only within the first two seconds after a power-on reset. An unrecoverable fault can occur anytime during operation.
Table 3-5 EXB-8500 States Indicated by LEDs
3.6 Setting the Write-Protect Switch
The EXATAPE™ 8mm data cartridge is equipped with a write-protect switch to prevent the tape from being written to unintentionally. Before loading a data cartridge in the EXB-8500, ensure that the write-protect switch is set correctly for the desired operation. You can use a ball-point pen or similar instrument to set the write-protect switch.
To write protect the data cartridge, move the write-protect switch away from the edge of the data cartridge, as shown in Figure 3-2. If the red tab is visible, the cartridge is write protected and cannot be written to or erased.
To write enable the data cartridge, move the write-protect switch toward the edge of the data cartridge, as shown in Figure 3-2. If the red tab is not visible, the data cartridge is write enabled and can be written to or erased.
Figure 3-2 Write-Protect Switch on EXATAPE 8mm Data Cartridge
3.7 Loading a Data Cartridge in the EXB-8500
To load a data cartridge into the EXB-8500, follow these steps:
1. Ensure that the write-protect switch has been set correctly for the desired operation. (See Section 3.6.)
2. If you have just powered on the EXB-8500, be sure that the green LED on the front panel is off, indicating that the EXB-8500 is ready to load the data cartridge.
3. If necessary, press the unload button to open the door on the EXB-8500.
4. Insert the data cartridge into the EXB-8500 with the label side up and the write-protect switch facing you.
5. Gently close the door. The EXB-8500 automatically loads the data cartridge and presents ready status (green LED on).
Note: If you have disabled autoload with a MODE SELECT
command, the EXB-8500 will not go to the ready state until a LOAD (1Bh) command has been executed.
Three options are available from EXABYTE to control how the EXB-8500 handles tape motion commands during the load operation. Depending on the EXB-8500’s EEPROM image, the EXB-8500 performs one of the following actions when it receives tape motion commands during a load operation:
It queues (holds) tape motion commands (and disconnects, if allowed) until the load operation is complete. Then it executes the commands.
It returns Busy status.
It returns Check Condition status with the sense key set to Not Ready.
Note: If another initiator has reserved the EXB-8500 for its exclusive use, the EXB-8500 returns Reservation Conflict status.
For information about these status conditions, see Section 7.4.
Load Time
The time required to load the data cartridge and position the tape to LBOT after the door is closed is approximately 30 seconds for a rewound cartridge.
When loading a tape, the EXB-8500 spaces forward from PBOT and
determines the tape format (blank, EXB-8500 format, or EXB-8200 format).
In addition, when the EXB-8500 spaces forward, it determines the adaptive servo parameters. This process enables the EXB-8500 to read tapes produced by different manufacturers, tapes that are aged and worn, and tapes written by other EXABYTE 8mm Cartridge Tape Subsystems.
Finally, during a load operation, the EXB-8500 autosizes the data cartridge (that is, it determines the length of the tape in use). For information about data cartridge autosizing, refer to Appendix C.
3.8 Unload Procedure
This section describes what happens when you press the unload button; for information about using the LOAD/UNLOAD (1Bh) command, see Chapter 10.