M2488 PRODUCT GUIDE

TAPE UNIT SCSI COMMANDS

Table 4-104. REPORT DENSITY SUPPORT Data Block Field Description

BYTE

BIT

VALUE

 

DESCRIPTION

 

 

 

 

 

0

0-7

 

 

The Primary Density Code contains the value returned by a MODE SENSE

 

 

 

 

command for the density described in the remainder of the DENSITY SUP-

 

 

 

 

PORT data block (reference the MODE SENSE command specification in sec-

 

 

 

 

tion XX for more information on density codes reported by MODE SENSE).

 

 

 

 

 

1

0-7

 

 

The Secondary Density Code field contains the equivalent density code value

 

 

 

 

when multiple density codes are assigned to the same recording technology

 

 

 

 

(density, format, capacity, etc.). If no secondary density code exists, then this

 

 

 

 

field is set to the Primary Density Code value in byte 0.

 

 

 

 

 

2

5

 

0

A Default (Deflt) bit of zero indicates this density is not the default density of the

 

 

 

 

logical unit.

 

 

 

1

A Deflt bit of one indicates this density is the default density of the logical unit.

 

 

 

 

 

2

6

 

0

A Dup bit of zero indicates this primary density code has exactly one DENSITY

 

 

 

 

SUPPORT data block.

 

 

 

1

A Dup bit of one indicates this primary density code is specified in more than

 

 

 

 

one DENSITY SUPPORT data block.

 

 

 

 

 

2

7

 

0

A Write OK (WrtOK) bit of zero indicates the logical unit support for this den-

 

 

 

 

sity does not include writing to the media.

 

 

 

1

A WrtOK bit of one indicates the logical unit is capable of writing this density to

 

 

 

 

either:

 

 

 

 

a) the currently mounted medium (Media bit in CDB is set to one), or

 

 

 

 

b) for some media (Media bit in CDB is set to zero).

 

 

 

 

 

5-7

 

 

 

The Bits per mm field indicates the number of bits per millimeter per track as

 

 

 

 

recorded on the medium. The value in this field shall be rounded up if the frac-

 

 

 

 

tional value of the actual value is greater than or equal to 0.5. A value of zero

 

 

 

 

indicates the number of bits per millimeter does not apply to this logical unit.

 

 

 

 

Direct comparison of this value between different vendors (possible prod-

 

 

 

 

ucts) is discouraged since the definition of bits may vary.

 

 

 

 

 

8-9

 

 

 

The Media Width field indicates the width of the medium supported by this den-

 

 

 

 

sity. This field has units of tenths of millimeters. The value in this field shall be

 

 

 

 

rounded up if the fractional value of the actual value is greater than or equal to

 

 

 

 

0.5.

 

 

 

 

 

10-11

 

 

 

The Tracks field indicates the number of data tracks supported on the medium by

 

 

 

 

this density. Direct comparison of this value between different vendors (pos-

 

 

 

 

sible products) is discouraged since the definition of the number of tracks

 

 

 

 

may vary.

 

 

 

 

 

April 1997

CG00000-011503 REV. A

4-109

Page 191
Image 191
Fujitsu M2488 manual Report Density Support Data Block Field Description