Fujitsu 7.1 M2488 Operation When Density Code 28h Is Not Configured, Density Code Description

M2488 PRODUCT GUIDE TAPE UNIT PARAMETERS

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):

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.

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):

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.

The Mode Sense command will report Density Codes in compliance with the following guide- lines:

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	Density Code 28h
no previous UNLOAD* has been performed.
When the unit is in the NOT READY state, and a previous UNLOAD* has	Density Code as reported in the most
been performed.	recent Mode Sense command.
After a Power Up sequence, when the unit is the READY state, but the tape	Density Code 28h
format has not yet been determined by the unit.

April 1997 CG00000-011503 REV. A 5-15