Quantum DLT 2500, Product Manual

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EEROM Resident Bugcheck and Event Logs
D-2 DLT2000/DLT2700 Cartridge Tape Subsystem
Bits 7 0
00
01
96
97
Packet Type
1st packet byte
last packet byte
/
/
/
/
/ .
.
.
.
. /
/
/
/
/
Packet Sequence Number
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.