6.2 Preparing for Communications
E5CK
6--3
6.2 Preparing for Communications
For details on wiring when using the communications, see Chapter 2 Prep-
arations.
J
Cable connections
•
Only one controller can be connected to the host computer.
•
The cable length should not exceed 15 meters.
•
Use shielded twisted-pair cables (AWG28 or more) for the cables.
RS-232C
No.
13 SD
RD
14
1 SG
E5CK
RS-232C
No.
13 SD
RD
14
1 SG
E5CK
IBM-PC/XT
DE-25
Female
DTE
(SD) TXD
(RD) RXD
(RS) RTS
(CS) CTS
(SG) COMMON
(ER) DTR
(DR) DSR
2
3
4
5
20
6
7
FG
1
(RD) RXD
(SD) TXD
(ER) DTR
(SG) COMMON
(RS) RTS
(CS) CTS
(DR) DSR
2
3
4
5
8
6
7
FG
1
25 pins
IBM-PC/AT
DE-25
Female
DTE
9 pins
•
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 120
Ω
(1/2 W). The total resis-
tance of both ends should be at least 54
Ω
.
-
+
FG
RS-485
No.
13
14
RS-485
No.
13 A
B
14
Host computer
RS-485
Shielded cable
E5CK (No.0)
E5CK (No.30)
Terminator (120
Ω
1/2W)
A
B
A < B : Mark
A > B : Space
F
RS-232C
F
RS-485