Omron SYSMAC CS1W-SCB41-V1 Operation Manual page 248

Protocol Conversion
Executing Smart Active Parts Using an NS-series PT (Sending Internal FINS Messages)
Access from PT on Ethernet or serial NT Link
NS-series PT
Smart Active Parts
FINS message (sent internally)
FINS header
Ethernet
Serial Communications Unit/Board
CPU Unit
Protocol
conversion
Modbus-RTU
command
ORMON Inverter
Note When the NS-series PT is connected serially to the
PLC using serial communications mode (1:N NT
Links), and the NS-series PT sends FINS com-
mands encapsulated in NT Link commands using
Smart Active Parts, the CPU Unit removes the NT
Link header, etc. from the received command, con-
verting it to a FINS command, and transfers the
command to the Serial Communications Board/
Unit. The Serial Communications Board/Unit uses
the Serial Gateway to convert the command into
the specified protocol. This operation enables seri-
ally connected devices to access the Serial Com-
munications Board/Unit from Smart Active Parts
using an NS-series PT.
Note
The Board/Unit converts the FINS messages to Modbus-RTU protocol for
sending in this operation.
Modbus-RTU
2804
command
RS-485 (Modbus-RTU)
(1) The FINS header contains the following information.
• Remote destination network address (DNA): Same as for CompoWay/F.
• Remote destination node address (DA1): Same as for CompoWay/F.
• Remote unit address (DA2): Same as for CompoWay/F.
(2) The contents of the Modbus-RTU command enclosed in the FINS mes-
sage that is sent is as follows:
Slave address (binary) + FUNCTION code (binary) + Communications
data (binary)
Start and CRC+End are not required when sending FINS. They are add-
ed automatically for serial communications.
Details
Access via serial communications using
Modbus-RTU is possible from a PT con-
nected to the network by executing a
Smart Active Part that is connected seri-
ally, which automatically sends an internal
FINS command.
Section 6-5
Routing tables
to treat serial
communications
path as network
Optional
219