Chapter 7 Board-control Commands

Page 7 - 6

 

Start Command List (01H)

Start Command List (01H)

Command

Format

With this command you can instruct the RF3880 adapter to begin operating from a Command List. Since with Command List operation you can attain higher performance from your SCSI peripheral, this is one of the first commands you should issue to the adapter. It must be issued by means of a Single Command Structure.

See Chapter 4, Command Operation for information about using Command Lists.

The Parameter Block Format for the Start Command List command looks like this:

Address

 

 

Byte Memory Address

 

 

Offset

Offset + 0

 

Offset + 1

 

Offset + 2

 

Offset + 3

 

 

 

 

 

 

 

 

 

 

 

00H

 

 

Command Identifier

 

 

 

 

 

 

 

 

 

04H

Reserved

 

 

Addr Mod

 

Adapter ID = FFH

 

 

 

 

 

08H

 

Command List Memory Address

 

 

 

 

 

 

 

0CH

Reserved

 

 

 

Interrupt

10H

Command = 01H

 

 

 

Reserved

 

 

 

 

 

 

 

 

 

 

14H

 

 

 

Reserved

 

 

 

 

 

 

 

 

 

18H

 

 

 

Reserved

 

 

 

 

 

 

 

 

 

 

Description of Fields

Table 60: Start Command List Parameter Block

Each of the fields used by the Start Command List command are explained in the following section:

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 field must always contain the ID of FFH to indicate a Board-control command.

Address Modifier

This is the value that the adapter is to drive onto the VMEbus Address Modifier Lines when selecting the memory address of the Command List.

Command List Memory Address

This field contains the address of the Command List in Memory. It points to the beginning of the structure: Parameter Block IN index.

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User’s Guide

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Ciprico Rimfire 3880 manual Board-control Commands Start Command List 01H, Start Command List Parameter Block, Adapter ID