National Instruments sbRIO-9605

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The first time you power up the device, it attempts to initiate a DHCP

network connection. If the device is unable to initiate a DHCP connection,

it connects to the network with a link-local IP address with the form

169.254.x.x. After powerup, you must install software on the device and

configure the network settings in Measurement & Automation Explorer

(MAX).

Note Installing software may change the network behavior of the device. For information

about network behavior by installed software version, go to

ni.com/info and enter the

Info Code

ipconfigcrio.

Connecting Serial Devices

NI sbRIO devices populated with RS-232 and RS-485 serial ports can

connect to devices such as displays or input devices. Use the Serial VIs to

read from and write to the serial port from a LabVIEW RT application. For

more information about using the Serial VIs, refer to the Serial VIs and

Functions topic of the LabVIEW Help.

Connecting CAN Networks

NI sbRIO devices populated with one IDC header provide connections to a

CAN bus. CAN-enabled NI sbRIO devices have pins for CAN_H and

CAN_L, which can connect to the CAN bus signals. The CAN port uses an

NXP PCA82C251T high-speed CAN transceiver that is fully compatible

with the ISO 11898 standard and supports baud rates up to 1 Mbps.

The port has two common pins (GND) that serve as the reference ground

for CAN_H and CAN_L. You can connect the CAN bus reference ground

(sometimes referred to as CAN_V–) to one or both COM pins. The port

also has an optional shield pin (SHLD) that can connect to a shielded CAN

cable. Connecting SHLD may improve signal integrity and EMC

performance.

CAN Bus Topology and Termination

A CAN bus consists of two or more CAN nodes cabled together. The

CAN_H and CAN_L pins of each node are connected to the main CAN bus

cable through a short connection called a stub. The pair of signal wires,

CAN_H and CAN_L, constitutes a transmission line. If the transmission

line is not terminated, signal changes on the bus cause reflections that can

cause communication errors. The CAN bus is bidirectional, and both ends

of the cable must be terminated. This requirement does not mean that every

node on the bus should have a termination resistor; only the two nodes at

the far end of the cable should have termination resistors.

National Instruments sbRIO-9605 - Page 39