7-2
Section
Using Message Communications
85
Similarly, the Master Unit attaches a FINS header to the response from the PT
and returns it to the CPU Unit as a FINS response.
CPU Unit
CMND
or
IOWR
Explicit
message
FINS
header
Use 28 01 for the
FINS command code.
FINS
header
Response
DeviceNet
Master Unit
FINS
header
FINS
header
Explicit
message
Response
DeviceNet
network
OMRON Slave
or another
manufacturer’s
Master or Slave
Reference When sending an explicit message, specify the DeviceNet Master Unit in the lo-
cal node as the destination of the FINS command. The final destination Slave
(PT) is specified in the command data of the FINS command.
7-2
Using Message Communications
This section explains how to use the FINS command (code 28 01) that sends
explicit messages as well as the CMND and IOWR instructions. Refer to 7-3
Explicit Messages for details on the contents of explicit messages.
7-2-1 EXPLICIT MESSAGE SEND (FINS Command 28 01)
The EXPLICIT MESSAGE SEND command is used to send an explicit Device-
Net message to the DeviceNet Master Unit.
Command Block
01
28
Destination node address
Service code
Instance ID
Service data
Class ID
Command
code
242 bytes max.
01
00
8A
00
Response Block
Normal Response
01
28
Source node address
Service code (see note)
No. of bytes
received
Service data
Response
code
Command
code
240 bytes max.
00
00
Note For a normal response, the leftmost bit of the service code specified in the com-
mand will be turned ON and then returned. For example, a command service
code of 32 Hex is returned as B2 Hex in the response.
Error Responses
The following response is returned if an error occurs for the explicit message.