SCSI Commands
Quantum DLT 7000 Tape System 5-161
SEND DIAGNOSTIC Command (1Dh) (continued)
Table 5–77 SEND DIAGNOSTIC Parameter List - Field Descriptions
Field Name Description
Pattern Number Indicates the type of data pattern to be used during the diagnostic tests.
Pattern
0
1
2
3
4
5
6
7
8
9 (default)
Name
Rotate
All 0s
2F
Alternating 1s and 0s
Marching 1
Marching 0
MW
MFM
IF
Random Data
Data in Hex
Rotate through the other 9 patterns;
change for each tape file.
00 00 00 00 00
FF FF FF FF FF
55 5A AA A5 55 5A AA A5
01 02 03 04 08 10 20 40 80
FE FD FB F7 EF DF BF 7F
0E 0E 0E 0E 0E 0E 0E 0E
DE AD DE AD DE AD DE AD
AA AA AA AA AA AA AA AA
Maximum Number
of Test Passes
This field specifies the number of test passes of the diagnostic to be run. If
Maximum Number of Test Passes = 0, the test will loop continuously. A
BUS RESET or a selection from the host sending an ABORT or BUS DEVICE
RESET message terminates testing. Default = 1
Block Size This field specifies the size of the blocks to be used. If this field is 0, random
block sizes are used. Default = 8400 bytes (DLTtape III media); 64 K
(DLTtape IV media).
Block Count This field specifies how many blocks to WRITE / READ to and from starting
on track 0, then moving to track 1. Default = 500.
For example, if the Block Size and Block Count fields result in three (3)
tracks worth of data, the test will:
Write tracks 0, 1, 2
REWIND, READ, and VERIFY tracks 0, 1, 2
WRITE three tracks starting with 1: 1, 2, 3 and then REWIND to the
beginning of track 1 and perform the READ and VERIFY pass.
If Block Count is = 0, data is written until EOT is reached each time, so
almost four (4) complete passes over the tape would result.