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Poll connection, Assembly object – “static, Table 10. assembly object instance attributes – Watlow Series SD6 Limit With Devicenet User Manual

Page 5: Table 9. assembly object revision history

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Table 10. Assembly Object Instance Attributes

Poll Connection

The poll connection allows the master to write set point and
process value in one connection. It also allows the reading of
all process value, set point and alarm status.

Table 11. Static Input – Instance 101 in the Assembly Object (total of 6 bytes)

Byte

Parameter and Description

Size of Data

Range

0

Exception Status Byte

Byte reserved for future use. (Required byte for
Semiconductor-Sig)

USINT

Always returns a value of zero.

1-4

Process Value

Actual value of process input

DINT

-1999.000 to 9999.000

5

Alarm Status

Indicates when alarm outputs are in alarm condi-

tion.

Breakdown of byte:

bit 0: limit low 1 status
bit 1: limit high 1 status
bit 2: limit or alarm low 2 status
bit 3: limit or alarm high 2 status

USINT

For each bit:

(0) None
(1)

Limit / Alarm

Instance #

Access Rule

Name

DeviceNet Data
Type

Description of
Instance

Semantics of
Values

100

Set

Poll Output

DINT + DINT +
USINT

Poll Output
(PLC to Controller)

See Table 11.

101

Get

Poll Input

USINT + DINT +
USINT

Poll Input
(i.e. Controller to
PLC)

See Table 12.

Attribute #

Access Rule

Name

DeviceNet Data
Type

Description of
Instance

Semantics of
Values

3

Get

Data

Array of BYTES

See description
below

See description
below

Class Services: GET ATTRIBUTE SINGLE

Instance Services: *SET ATTRIBUTE SINGLE (when
MACID or BAUD RATE in PRG MODE), GET
ATTRIBUTE SINGLE, ALLOCATE M/S CONNECTION
SET, RELEASE M/S CONNECTION SET.

Assembly Object – “Static”

Class Code: 04hex

The Assembly Object binds attributes of multiple objects,
which allows data to or from each object to be sent or
received over a single connection. Assembly objects can be
used to bind input data or output data. The terms “input”
and “output” are defined from the network’s point of view.

An input will produce data on the network and an output
will consume data from the network.

The term “Static” implies: assemblies with member lists
defined by the device profile or by the manufacturer of the
product. The Instance number, number of Members, and
member list are fixed.

Table 9. Assembly Object Revision History

Revision

Description

01

Initial Release

02

Class-specific Service Code 4B
and 4C obsolete