National Instruments PCI-8430, Manual

Page: 108 / 237

Setting the RS-485 Transceiver Control Mode in
LabVIEW Real-Time
Setting the Default Mode of Operation
To set the default mode of operation:
For PXI:
Use the Advanced tab in Measurement & Automation Explorer
(MAX) to define the default transceiver control mode.
For FieldPoint devices supporting multiple transceiver control
modes, follow these steps:
Note Without modification, the default mode is set to four-
wire.
1. Using an FTP client, download the
/ni-rt/system/niserial.dbs
file from the LabVIEW Real-Time target.
2. Locate the entry in the
niserial.dbs
file that says
SerialPortName = "COM x "
, where
COM x
corresponds to the
port you want to modify.
3. In the next line, add the following entry to the
niserial.dbs
file:
TransceiverMode =
<Transceiver Mode>
where
<Transceiver Mode>
is:
<Transceiver
Mode>
Description
128 Four-wire mode
129 Two-wire mode: DTR controlled with
echo
130 Two-wire mode: DTR controlled