HP 9000 Series, Service Manual

Page: 325 / 472

Chapter 11 11- 29
SCSI Peripherals and I/O Information
The front panel of the C2478SZ is used for inserting and removing cassette tapes, and displaying drive
and cassette status. The front panel has two bi-color lights (LEDs). The green is used to indicate
normal operation. Amber is used to imply warning conditions. Pulsing indicates activity between the
drive and the SCSI bus. If the Cassette light shows steady amber, this indicates that the cassette is
write protected. If the Drive light shows steady amber, this indicates a fault condition. Refer to Figure
11-9 for a list of indicator combinations and definitions.
Figure 11-9 Cassette and Drive Light Definitions
Media wear (caution) - indicates head cleaning is needed. This is an indication of an excessive
number of Read-After-Write (RAW) or third level error correction (C3 ECC) errors. This condition
can be caused by dirty heads or by a cartridge approaching the end of its life. If the flashing light
reoccurs after the initial cleaning, the data cartridge involved should be removed from use by reading
the data from the tape and copying that data to a new tape. The indication is only cleared by
completing a cleaning cycle, no matter what the cause is, however, the indication does not stop the
activity of the tape unit.