Setting The Communications Specifications - Omron E5AK User Manual

CHAPTER 6 USING THE COMMUNICATIONS FUNCTION
F RS-485
Host computer
RS-485
-
+
FG
J Setting the com-
munications
specifications
F Communications
parameters
Unit No.
Baud rate
Bit length
Parity
Stop bit
6--4
· Up to 32 controllers including a computer can be connected to the host
computer.
· The total cable length should not exceed 500 meters.
· Use shielded twisted-pair cables (AWG28 or more) for the cables.
· Attach terminators to the controllers at both ends of a series of control-
lers connected in an open configuration. For example, in the following
configuration, connect the terminator to the host unit and the unit
No.30, and do not connect terminators to unit Nos.0 to 29.
· Use terminators having a resistance of 120W (1/2 W). The total resis-
tance of both ends should be at least 54W .
Shielded cable
Match the communications specifications of the host computer and E5AK
controller. When two or more controllers are connected to the host com-
puter, make sure that the communications specifications of all controllers
are the same.
This section describes how to set the communications specifications of the
E5AK controller. For details on the host computer, see the relevant manual
supplied with the host computer.
Set the communications specifications of the E5AK in the controller's
communications parameters. The communications parameters are set on
the front panel of the E5AK controller.
The following table shows the communications parameters (option mode)
provided on the E5AK controller and their respective settings.
Parameter/Symbol
A < B : Mark
A > B : Space
E5AK (No.0)
RS-485
No.
32 A
31 B
19 A
B
20
Setting
0 to 99
1.2/2.4/4.8/9.6/19.2 (kbps)
7/8 (bit)
None/even/odd
1/2
Terminator
(120W 1/2W)
E5AK (No.30)
RS-485
No.
32 A
B
31
19 A
B
20
Set Value
0 to 99
1.2/2.4/4.8/ 9.6 /19.2
7 /8
/ /
1/ 2
Inverted items are factory-settings.