Delta RMC151 - Manual (Page 554)

RMC70/150 and RMCTools User Manual
Wires 3 2 + CMN
Max Length 2 50-100 ft 4000 ft
Note:
The maximum cable lengths vary depending on the baud rate, termination (for RS-485), and
capacitance of the cable. See the RS-485 Termination and Biasing topic for details.
Each of the above features is described below:
Duplex (Full or Half)
Full-duplex means that each device on a serial network can send and receive at the same
time, effectively doubling the bandwidth of the network. Half-duplex means that only one
device on the network can send data at one time. For the above drivers, full-duplex
requires separate send and receive wires.
Differential
Differential wiring uses two wires per signal which allows common mode noise
rejection. RS-232 does not use differential wiring, but instead has one wire per signal plus
a ground. Differential wiring allows for longer cable distances and greater noise immunity.
Topology
Topology describes the layout of the network. Point-to-point means that exactly two
devices are wired together. Multi-drop means that two or more devices are chained
together. Notice that "multi-drop" with only two devices becomes point-to-point. See
Serial Network Topologies for details.
Wires
This item refers to how many wires need to be connected between nodes. Notice that 2-
wire actually requires three because of the Common in addition to the differential signal
wires. See RS-232 Wiring for the RMC SERIAL and RS-485 Wiring for the RMC SERIAL for
details.
Max Length
The maximum cable lengths vary depending on the baud rate, termination (for RS-485),
and capacitance of the cable. See the RS-232 Wiring for the RMC70 and RS-485 Wiring
for the RMC70 topics for details.
Flow Control
Flow control can be used with RS-232 to ensure that one device does not overrun the
other device. That is, if one device is sending data and the receiving device's buffers get
full, then it can use flow control to pause the first device's sending until it has room in its
buffers.
6.10.3.2. Configuring the RMC75S Serial Communications
The RMC75S port 1 supports most standard serial port options, several protocols, and several
line drivers. These settings can be changed using RMCTools and saved to Flash memory.
The Monitor port (port 0) settings are fixed. See the Monitor Port topic for details.
Changing Serial Settings
To change the serial communication settings:
1. In the Project pane, expand the Modules folder, double-click the module with serial
communications, and then click Serial.
2. Make the desired changes. For a description of the options, see the Configuration
Options section in this topic.
534 Delta Computer Systems, Inc.