Quantum DLT 4700, Product Manual

Page: 344 / 360

EEROM Resident Bugcheck and Event Logs
D-2 DLT4000/DLT4500/DLT4700 Cartridge Tape Subsystem
Figure D-1 EEROM Log Area Layout
Table D-1 EEROM LOG Packet Types
Packet Purpose
Type
0 Packet Empty
1 Bugcheck - Fatal System Crash
2 PO/ST (power on/self test) Failure
3 EVENT LOG - Generic event informational (non-fatal) data
4 CUP - Code Update Status Packet
5 Manufacturing DIAG results packet
D.2 Bugcheck Packets
Bugchecks occur because of some kind of software detected fatal failure. For
example, a hardware failure, or an internal system consistancy failure might cause a
bugcheck. These events cause Bugcheck packets to be written into EEROM. Refer to
Figure D-2 for the detailed packet layout. The most important information is the
error code. The more common ones are listed in Table D-2. A full listing is not given
here because most are not meaningful without a detailed knowledge of the firmware
design. Analysis of the other informtion saved in an EEROM Bugcheck log entry
also requires in-dpth internal firmware knowledge to interpret and attempt to
determine if the cause was external (e.g. a bad SCSI bus cable, improper
termination, etc.), an ECM or drive fault, or a firmware bug.