M2488 PRODUCT GUIDE TAPE UNIT PARAMETERS
April 1997 CG00000-011503 REV. A 5-15
5-2.7.1 M2488 Operation When Density Code 28h Is Not Configured
In its default mode, the M2488 does not use Density Code 28h. The Mode Select command will
accept the following settings in the Density Code field (Mode Parameter Block Descriptor Byte
00h):
Regardless of the Density Code setting used in the Mode Select command, the Mode Sense com-
mand will always report a Density Code value of 09h.
5-2.7.2 M2488 Operation When Density Code 28h Is Configured
Once the DENSITY_CODE_28H feature mode has been configured, the Mode Select command
will accept the following settings in the Density Code field (Mode Parameter Block Descriptor
Byte 00h):
The Mode Sense command will report Density Codes in compliance with the following guide-
lines:
Table 5-14. Density Code Settings Accepted by Mode Select Command in Default Operation
DENSITY CODE DESCRIPTION
00h Write tapes in 36T format.
Read tapes in 18T and 36T formats.
09h Write tapes in 36T format.
Read tapes in 18T and 36T formats.
7Fh Retain current Density Code setting.
Table 5-15. Density Code Settings Accepted by Mode Select Command with Density Code 28h
Configured
DENSITY CODE DESCRIPTION
00h Write tapes in 36T format.
Read tapes in 18T and 36T formats.
09h Write tapes in 36T format.
Read tapes in 18T and 36T formats.
28h Write tapes in 36T format.
Read tapes in 18T and 36T formats.
7Fh Retain current Density Code setting.
Table 5-16. Density Codes Reported by Mode Sense Command with DENSITY_CODE_28H Configured
WHEN THE FOLLOWING IS TRUE MODE SENSE WILL REPORT
After a Power Up sequence, while the unit is in the NOT READY state and
no previous UNLOAD* has been performed. Density Code 28h
When the unit is in the NOT READY state, and a previous UNLOAD* has
been performed. Density Code as reported in the most
recent Mode Sense command.
After a Power Up sequence, when the unit is the READY state, but the tape
format has not yet been determined by the unit. Density Code 28h