Explanation; Serial Communications Path (Host Link Fins); Unit Address - Omron CJ - REFERENCE MANUAL 07-2009 Reference Manual

Serial Gateway Overview

3-6-10 Explanation

Unit Addresses for Serial
Communications Ports
84
To treat the serial communications path as a network, the serial port itself is
recognized as a Communications Unit and is allocated a network address.
CPU Unit
Peripheral port

Unit address:

253 (decimal)
RS-232C port
Unit address:
252 (decimal)
Serial communications path
Assigned to network address n
Serial Communications Unit/Board
Serial port
Unit address U
(See note.)
Serial communications path
Assigned to network address n
The CX-Net in the CX-Programmer is used to set the relationship between the
serial port's unit address and the allocated network address in the local net-
work tables of the routing tables. These settings are then transferred to the
CPU Unit to which the Serial Communications Unit/Board is mounted.
CX-Net in CX-
Programmer
Serial Communications Unit/Board
Serial communications path
Unit address U (80 hex/81 hex
+ unit number × 4 hex)
CS/CJ Series CPU Unit
CPU Unit
Peripheral port
RS-232C port
Serial communications port on
CPU Unit
Peripheral port
RS-232C port
Commu-
Local network table in routing tables
nications
Ex-
Unit number
Unit
pressed
(See note.)
as:
Note: The unit number is set as a
Network
Commu-
Local network table in routing tables
nications
Ex-
Unit number
Unit
pressed
(See note.)
as:
Note: The unit number is set as a
Network
Local network table in routing tables
Unit number
U
PC
Local
network
table
Network address n
Unit address
FD hex (253 decimal)
FC hex (252 decimal)
Section 3-6
Network
address
252 n
Set correspondence
CPU Bus Unit for Communica-
tions Units, but the unit address
is set for the serial port.
• Peripheral port: 253 (decimal)
• RS-232C port: 252 (decimal)
Network
address
U n
Set correspondence
CPU Bus Unit for Communica-
tions Units, but the unit address
(80 hex/81 hex + unit number ×
4 hex, as a decimal) is set for
the serial port.
Network
address
n
Set the unit address
U as a decimal for
the unit number.