Introduction - Pepperl+Fuchs AS-I 3.0 Manual

AS-i 3.0 Command Interface

Introduction

1. Introduction
The AS-i gateways integrate the AS-i slaves into the upstream fieldbus. Each up-
stream fieldbus (f.e. Modbus/TCP, CANopen, or PROFIBUS) has its unique pos-
sibilities to access cyclically and acyclically data. The gateway polls as an AS-i
master all the slaves on the AS-i circuit. The result of these polls the gateway
keeps in its internal state RAM as images of the inputs, outputs, parameters, and
status. These images are available for use on the upstream fieldbus with their
specific access methods. The images of the Modbus/TCP to AS-i gateway are
available with Modbus Read and Write function calls on different Modbus regis-
ters. The main manual (command: insert cross reference) describes this in detail.
CANopen provides this access with PDOs for cyclical access and SDOs for acy-
clical access.
The access to the images of the gateway is easy to configure on the upstream
fieldbus and in most applications sufficient. However, the complete functionality of
the gateway is available with the command interface. If you want to read the diag-
nosis string of an AS-i tuner (slave with 7.4 profile), you will need the command
interface to call the WRITE_ACYC_DATA and READ_ACYC_DATA commands.
The command interface is avaible in a special image. A command is called by
writing into this image and the command result is avaible with a read to this im-
age.
Information!
The manual "AS-i 3.0 Command Interface" describes commands of the AS-i 3.0 Com-
mand Interface. A description of an AS-i Master is not included. Please refer to the cor-
responding manual of your AS-i Master for further information.
Please view the documentation of the respective device for further, device-specific
information about the kind of the access to the command interface.
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