Chapter 7 Board-control Commands

Extended Unit Options (18H)

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Extended Unit Options (18H)

Command

Format

This command, in either initiator or target mode, is designed as an enhancement to the Unit Options command. The primary difference between the commands is the opportunity to select 16 bytes of Sense Data to be returned per unit, instead of the eight offered in the Unit Options command.

Another difference is that the Extended Unit Options for the SCSI device are built into a Data Structure whose address is simply passed in the command.

The format of the Extended Unit Options command is as follows:

Address

 

 

Byte Memory Address

 

Offset

Offset + 0

 

Offset + 1

 

Offset + 2

Offset + 3

 

 

 

 

 

 

 

 

 

00H

 

 

Command Identifier

 

 

 

 

 

 

 

04H

Reserved

 

 

Addr. Mod.

Adapter ID = FFH

 

 

 

 

 

 

08H

 

 

VME Memory Address

 

 

 

 

 

 

 

0CH

 

 

 

Reserved

 

10H

Command = 18H

 

 

 

Reserved

 

 

 

 

 

 

 

 

14H

 

 

 

Reserved

 

 

 

 

 

 

 

18H

 

 

 

Reserved

 

 

 

 

 

 

 

 

Description of Fields

Table 103: Extended Unit Options Parameter Block

Each of the fields of the Parameter Block are described below:

Command Identifier

The Command Identifier field is used to identify the Status Block associated with a Parameter Block. It must be a unique value.

Adapter ID

This is a Board-control command. The value in this field must be FFH.

Address Modifier

This is the value to be used by the adapter on the Address Modifier lines when reading the Extended Unit Options Data Structure from memory.

VME Memory Address

This is the system memory address at which you have built the Extended Unit Options Data Structure.

Command Code

The value for this field will always be 18H to indicate a Extended Unit Options command.

The format of the Data Structure to be used for the Extended Unit Options command is illustrated on the following pages.

User’s Guide

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Ciprico Rimfire 3880 manual Board-control Commands Extended Unit Options 18H, Extended Unit Options Parameter Block