TAPE UNIT SCSI COMMANDS M2488 PRODUCT GUIDE
4-6 CG00000-011503 REV. A April 1997
Definition parameter values of 00h and 03h have no effect on the target since this is the normal
operating definition for this product. These values are accepted to maintain ANSI compliance.
Definition parameter 40h selects INQUIRY Vital Product Data (VPD) Page code C2h and is used
to change the Product Identification data that is reported in standard INQUIRY bytes 8 through 31.
This data includes Vendor ID, Controller Product ID and Logical Unit Product ID. This value will
be accepted at any time. Using this parameter has little effect on target operation in that it only
changes constant data returned by the INQUIRY command.
Definition parameter 41h is intended for factory use and will be accepted only if the target is in
factory mode. Change Definition data sent in this mode includes INQUIRY VPD pages 80h, C0h,
C1h and C2h. This data contains such information as Unit Serial Number, Unit Usage Data, Unit
Configuration and Product Identification Data. Using this parameter may cause the target to
appear not operational and have serious side effects.
4-3.2.2 CHANGE DEFINI TION Changes
It is suggested that the required page is first obtained from the target via the Inquiry command,
data is then changed to the desired value and the data returned to the target via Change Definition
in the same format as it was received.
Single or multiple pages may be sent with a single Change Definition data transfer. The target will
not accept partial pages or pages not defined as changeable. The pages may be sent in any order
but must be of correct format and length.
The requested changes to the VPD pages will take effect as follows:
a. Changes to VPD page 80h Unit Serial Number Page and C2h Product Identification Page
take effect following a hard reset condition, i.e.; power-on, Bus Device, or SCSI bus reset.
b. Changes to VPD page C0h Unit Usage Page take effect upon the successful completion of
the CHANGE DEFINITION command.
80-7
0
>0
The Parameter Data Length specifies the length in bytes of the parameter data that shall be
transferred from the initiator to the target.
A parameter data length of zero indicates that no data shall be transferred. This condition
shall not be considered an error.
Parameter data lengths greater than zero indicate the number of bytes of parameter data
that shall be transferred.
The data that may be transferred is defined in section 5-3 for the MTU device and section
6-4 for the Media Changer device and consists of Vital Product Data Pages that may be
read via the Inquiry command.
Table 4-4. Definition Parameter Description
VALUE MEANING OF DEFINITION PARAMETER
00h Use current operating definition.
03h SCSI-2 operating definition.
40h Change user product data.
41h Change factory product data.
Table 4-3. CHANGE DEFINITION Field Description (Continued)
BYTE BIT VALUE DESCRIPTION