RS–485 Network (Modbus only)
RS–485 signals are for longer distances (1000 meters max.), and for multi-drop networks.
Use termination resistors at both ends of RS–485 network wiring, matching the impedance
rating of the cable (between 100 and 500 ohms).
RS–232 Network
Normally, the RS–232 signals are used for shorter distances (15 meters max), for
communications between two devices.
DL205 User Manual, 4th Edition, Rev. B
4–47
Chapter 4: System Design and Configuration
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
Port 2 Pin Descriptions (DL260 only)
1
5V
5 VDC
2
TXD2
Transmit Data (RS-232)
3
RXD2
Receive Data (RS-232)
4
RTS2
Ready to Send (RS–232)
5
CTS2
Clear to Send (RS–232)
6
RXD2–
Receive Data – (RS–422/RS-485)
7
0V
Logic Ground
8
0V
Logic Ground
9
TXD2+
Transmit Data + (RS–422/RS–485)
10
TXD2 –
Transmit Data – (RS–422/RS–485)
11
RTS2 +
Request to Send + (RS–422/RS–485)
12
RTS2 –
Request to Send – (RS–422/RS–485)
13
RXD2 +
Receive Data + (RS–422/RS–485)
14
CTS2 +
Clear to Send + (RS422/RS–485)
15
CTS2 –
Clear to Send – (RS–422/RS–485)
DL260 CPU Port 2
TXD+ / RXD+
TXD– / RXD–
T
ermination
Resistor
Signal GND
Cable: Use AutomationDirect L19954
(Belden 9842) or equivalent
TXD+
TXD–
RXD–
7
10
15
RXD+
0V
6
11
TXD+
TXD–
RXD–
7
10
15
RXD+
0V
1
5
11
TXD+ / RXD+
TXD– / RXD–
Signal GND
TXD+ / RXD+
TXD– / RXD–
Signal GND
R TS+
R TS–
CTS+
CTS–
R TS+
R TS–
CTS+
CTS–
DL260 CPU Port 2
5
1
6
Signal GND
RXD
1
5
10
11
15
TXD
7
2
3
4
TXD
RXD
GND
RTS
CTS
RTS
CTS
6
CPU Port 2
ASCII Device
ý
ý
ý
þ
230
240
2
5
0
-1
2
6
0
