TAPE UNIT SCSI COMMANDS

M2488 PRODUCT GUIDE

 

 

Table 4-3. CHANGE DEFINITION Field Description (Continued)

 

 

 

 

 

 

 

BYTE

BIT

VALUE

 

DESCRIPTION

 

 

 

 

 

 

 

8

0-7

 

 

The Parameter Data Length specifies the length in bytes of the parameter data that shall be

 

 

 

 

transferred from the initiator to the target.

 

 

0

A parameter data length of zero indicates that no data shall be transferred. This condition

 

 

 

 

shall not be considered an error.

 

 

>0

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.

 

 

 

 

 

 

 

 

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 DEFINITION 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.

4-6

CG00000-011503 REV. A

April 1997

Page 88
Image 88
Fujitsu M2488 manual Definition Parameter Description, Change Definition Changes, Value Meaning of Definition Parameter