HP C2488A Technical Reference Manual page 74

Mode Select, Mode Sense'>
DBD (Dbable Block Ueseriptors).This field 'indicates whether or not the target will return
any block descriptors. A DBD bit of:zero (0) indicates that zero or more block descriptors will
be returned. A DBDbit of one (l)jndicates that no block descriptors will be returned.
PC (Page Control). This field defines the Parameter Page type to be returned. The supported
values for this field are:
00
=
Report Current Values: Returns the parameters set in the last successful MODE
SELECT command; or the saved values if a MODE SELECT command has not been
executed since the last Power On, Hard Reset, or Bus Device Reset; or the default values if
saved values are not available.
01
=
Report Changeable Values: The changeable values are listed in the Parameter Values
table that follows each of the page format tables.
10
=
Report Default Values: The default values are listed in the Parameter Values table
that follows each of the page format tables.
11
=
Report Saved Values: Returns the saved values of the requested Parameter Pages.
(Savable Pages are indicated in the following table and in the title block for each page
format ta.ble.) The Save Block size is reported in the Block Length field of the Block
Descriptor.
Page Code. This field specifies which page(s) are to be returned to the initiator. The target
supports the following Mode Sense page codes:
Page Code
OOH
OIH
02H
03H
04H
OSH
09H
OAH
3FH
Description Savable
Retwn No Pages nfa
Error Recovery Parameters Yes
Device Disconnect/Reconnect Parameters Yes
Direct Access Device Format Parameters Yes
Rigid Disk Drive Geometry Parameters No
Cache Control Parameters Yes
Peripheral Device Parameters
Control Mode Parameters
Retwn All Pages
Yes
Yes
n/a
Allocation Length. This field specifies the number of bytes that the initiator has allocated for
returned MODE SENSE data. An Allocation Length of zero indicates that no MODE SENSE
data will be transferred. This condition is not considered an error. Any other value indicates
the maximum number of bytes that will be transferred. The target will terminate the Data In
phase when the specified number of bytes have been transferred or when all available MODE
SENSE data have been transferred to the initiator, whichever is less.
A·18 SCSI Command Descriptions
DRAFT
1/18/93 09:58