Omron E5ZN-DRT, Operation Manual

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Overview of Explicit Message Communications Section 6-1
6-1-2 Explicit Messages Types
The explicit messages sent to the DeviceNet Communications Unit can be
divided into two types, as follows:
Sending
CompoWay/F
Communications
Commands to
Temperature
Controllers
The master can send CompoWay/F communications commands to the Tem-
perature Controllers by sending to the DeviceNet Communications Unit as
explicit messages data.
The DeviceNet Communications Unit automatically converts the explicit mes-
sages to CompoWay/F communications commands and sends them to the
Temperature Controllers. The responses from the Temperature Controllers
are converted into explicit messages and returned to the master. Compo-
Way/F commands are used to read from and write to the Temperature Con-
troller variable area and to execute operation commands.
CompoWay/F commands consist of binary commands and ASCII commands.
CompoWay/F Binary
Commands CompoWay/F binary commands are CompoWay/F communications com-
mands expressed in hexadecimal, and are easy to execute from ladder pro-
grams. CompoWay/F communications commands that include ASCII data,
however, cannot be sent or received. Therefore, Read Controller Attribute (05
03) and broadcasting (unit number = XX) cannot be used.
CompoWay/F ASCII
Commands CompoWay/F ASCII commands are CompoWay/F communications com-
mands expressed in ASCII, so numerical values must be converted to ASCII
when executing these commands from a ladder program. All CompoWay/F
communications commands can be sent and received, including Read Con-
troller Attribute (05 03) and broadcasting (unit number = XX), which cannot be
used with CompoWay/F binary commands.
Sending Explicit
Messages to the
DeviceNet
Communications Unit
The master can send explicit messages to the DeviceNet Communications
Unit to control various operations supported by the DeviceNet Communica-
tions Unit and to read settings and status information.
Explicit messages are used to read and write various maintenance data for
the DeviceNet Communications Unit and Temperature Controllers.
6-1-3 Explicit Messages Basic Format
The basic format of explicit message commands and responses is as follows:
Command Block
Destination Node Address This parameter specifies the node address of the DeviceNet Communications
Unit to which the explicit messages (commands) will be sent in single-byte (2-
digit) hexadecimal.
Service Code, Class ID,
Instance ID, Attribute ID These parameters specify the command type, processing target, and pro-
cessing details.
When sending explicit messages to the DeviceNet Communications Unit,
specify the target Temperature Controller in the Instance ID. (Specify the Tem-
perature Controller’s unit number and channel number).
The Attribute ID does not need to be specified for some commands.
Data Specifies the details of the commands and set values. The data section is not
required for read commands.
Destina-
tion node
address
Service
code
Class ID
Instance
ID
Attribute
ID
Data