Single command structure, Format of single command structure, Table 20: single command structure – Ciprico Rimfire 3880 User Manual

Page 67

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User’s Guide

21020285 D

Chapter 4 Command Operation

Single Command Structure

Page 4 - 9

Single
Command
Structure

There are two ways to issue a command to the RF3880 adapter. The simplest
method involves the use of the Single Command structure. This 52-byte
structure combines a Parameter Block and a Status Block into a single structure
along with a field that specifies an interrupt level and ID. This Single Command
structure is shown below. The important things to remember about the Single
Command structure are:

It is designed to be used for initial set-up.

The first command you issue to the board after power-up or reset must
use this structure.

Format of

Single

Command

Structure

The Single Command structure is illustrated for you below:

Parameter Block

This section of the Single Command structure is where you build a Parameter
Block containing information related to the command you wish to execute:
Initiator Pass-through or Board-control.

Most of the fields are command-specific; if there is data to transfer, for example,
an address, address modifier and transfer count must be provided. For details
about the parameter block fields necessary for a Initiator Pass-through
command refer to Chapter 5, Initiator Pass-through Commands and a SCSI
specification. For details about a Board-control command see Chapter 7, Board-
control Commands.

Reserved Fields

Reserved fields must be zeroed. If a non-zero value is permitted in a Reserved
block, you may get an error.

Address

Offset

Byte Memory Address

Offset +0

Offset +1

Offset +2

Offset +3

00H

Parameter Block

(detail for Initiator Pass-through commands on page 5 - 3,

see Chapter 7 for details on individual Board-control commands.)

04H

08H

0CH

10H

14H

18H

1CH

Reserved

Reserved

20H

Reserved

24H

Status Block

(detail for Initiator Pass-through status on page 5 - 12,

see Chapter 7 for detail on individual Board-control status.)

28H

2CH

30H

Table 20: Single Command Structure

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