Page
14
LTO SCSI Interface Manual
Message exception handling
Message exceptions are handled as described in the following tables. The numbers
in the tables identify the actions that the drive takes when an exception under the
identified conditions occurs. The actions are listed following the tables.
Phase During Which ATN is Raised
Message
Selection
Ident.
Cmd
Data in
Data out
Status
sdtr/wdtr
Abort (06h)
2
2
2
2
2
2
2
BDR (0Ch)
2
2
2
2
2
2
2
Identify
(80h/C0h)
12
7, 11
7, 11
7, 11
7, 11
7, 11
7, 11
IDE (05h)
5
2
If Retry, 8,
else 5
If Retry, 8,
else 5
If Retry, 8,
else 5
If Retry, 8, if
Status, 2, if
No Status,
5
If Retry, 4,
else 5
Reject (07h)
5
2
2
2
2
2
1
Parity (09h)
5
2
11
11
11
11
If Retry, 4,
else 5
NOP (08h)
5
9
9
9
9
9
If EOM, 9,
else 4
SDTR
5
10
7, 11
7, 11
7, 11
7, 11
10
WDTR
5
10
7, 11
7, 11
7, 11
7, 11
10
Unrecognized
or illegal
5
6
6
6
6
6
If EOM, 6,
else 4
Message-In Byte During Which ATN is Raised
Message
SDP
(02h)
Restore
Pointers
(03h)
Disconnect
(04h)
Reject
(07h)
Identify
(80h)
CC
(00h)
Ignore
Wide Resi-
due
(23h)
Abort (06h)
2
2
2
2
2
2
2
BDR (0Ch)
2
2
2
2
2
2
2
Identify
(80h/C0h)
7, 11
7, 11
7, 11
7, 11
7, 11
2
7, 11
IDE (05h)
If Retry, 4
else 5
If Status, 2,
if No Status,
5
If Retry, 4,
else 5
If Retry, 4,
else 13
If retry, 4,
else 5
2
If retry, 4,
else 5
Reject (07h)
2
If Status, 2,
if No Status,
5
1
2
2
2
2
Parity (09h)
If Retry, 4
else 5
If Status, 2,
if No Status,
5
If Retry, 4,
else 5
If Retry, 4,
else 13
If Retry, 4,
else 5
2
If Retry, 4,
else 5
NOP (08h)
9
9
9
9
9
2
If EOM, 9,
else 4
SDTR
7, 11
7, 11
7, 11
7,11
7, 11
2
7, 11
WDTR
7, 11
7, 11
7, 11
7,11
7, 11
2
7, 11
Unrecognized
or illegal
6
6
6
6
6
2
If EOM, 6,
else 4
Retry
Retry has not been exhausted
EOM
End of the message
Status
Status has been reported
No Status
Status has not been reported
