ProSoft Technology MVI94-MCM-MHI - Manual (Page 69)

MVI94-MCM ♦ Flex I/O Platform Reference
Serial Communications Modbus Communication Module User Manual
ProSoft Technology, Inc. Page 69 of 109
March 29, 2011
RS-232: Null Modem Connection (Hardware Handshaking)
This type of connection is used when the device connected to the module
requires hardware handshaking (control and monitoring of modem signal lines).
RS-232: Null Modem Connection (No Hardware Handshaking)
This type of connection can be used to connect the module to a computer or field
device communication port.
Note: For most null modem connections where hardware handshaking is not required, the Use
CTS Line parameter should be set to N
and no jumper will be required between Pins 7 (RTS) and 8
(CTS) on the connector. If the port is configured with the Use CTS Line set to Y, then a jumper is
required between the RTS and the CTS lines on the port connection.