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Watlow Series SD6 Limit With Devicenet User Manual

Series sd6 limit with devicenet, Devicenet communications, Devicenet overview

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Series SD6 Limit with DeviceNet

Table 2. Descriptions of DeviceNet Elementary Data Types used by the Series SD

Data Type Name

Data Type Description

BOOLEAN

Logical Boolean with values TRUE and FALSE

BYTE

Bit string — 8 bits

EPATH

DeviceNet path segments

INT

Signed 16-bit integer value

SHORT_STRING

Character string (1 byte per character, 1 byte length indicator)

UDINT

Unsigned 32-bit integer value

UINT

Unsigned 16-bit integer value

USINT

Unsigned 8-bit integer value

This appendix describes the DeviceNet protocol as it is
implemented in the Series SD6 controller. It primarily
describes the objects and attributes accessible via the
DeviceNet protocol. It may be necessary to refer to the
DeviceNet specification as a compliment to the information
found here.

DeviceNet Overview

The SD6 controller supports the object-based modeling
used in the DeviceNet concepts. This product is configured
as a Group 2 Only Slave device using the Predefined
Master/Slave Connection Set.

There are two main categories of objects, DeviceNet
Objects and Application Objects. DeviceNet objects handle
what is necessary for networking and communications.
Application Objects have access to the SD6 controller's
parameters and data.

Addressing

All data is referenced based upon a four-part definition:
Node (MAC ID) + Class + Instance + Attribute.

Table 1. Four Components to an Address, with
Ranges

Node Address (MAC ID)

[0 to 63]

Class ID

[1 to 255]

Instance ID

[0 to 255]

Attribute ID

[1 to 255]

Data Types

The descriptions of attributes in the following sections
include the data type for each. Table 5 lists and describes
these data types.

DeviceNet Communications

0600-0041-0016

Rev B May 2005

This document is available as an Adobe Acrobat PDF file at
www.watlow.com; search on “SD6 DeviceNet”.