Emerson ControlWave EFM Instruction Manual page 55

RS-232 COM
Port Cables
Revised Dec-2013
For the ControlWave EFM, half-duplex communications use Modbus or
BSAP protocol, while full-duplex communications use point-to-point
protocol (PPP). RS-232 ports use a "null modem" cable (see Figure 2-
22) to connect with other devices (such as a PC, a printer, another
ControlWave [except the CW_10/30/35]) when the ControlWave EFM
uses the full-duplex PPP protocol.
: You can configure the ControlWave EFM as either a master or
Note
slave node on a Modbus or BSAP network.
Figure 2-21 illustrates the CPU module's male 9-pin D-type connector.
Use the content provided in Table 2-8 to determine pin assignments for
the COM1 and COM2 ports and the expansion communication ports
COM4/5 and COM8/9.
Figure 2-21. Male DB9 9-Pin Connector
Table 2-10. RS-232 Port Connector Pin Assignment
Pin
1
2
3
4
5
6
7
8
9
Use the "null modem" cable for full-duplex (PPP protocol)
communications when connecting a ControlWave EFM to a PC. (See
top part of Figure 2-22.)
Installation
ControlWave EFM Instruction Manual
RS-232
Signal RS-232 Description
DCD Data Carrier Detect Input
RXD Receive Data Input
TXD Transmit Data Output
DTR Data Terminal Ready Output
GND Signal/Power Ground
DSR Data Set Ready Input
RTS Request to Send Output
CTS Clear to Send Input
N/A
2-35