NI CAN Bus Interfaces

NI CAN bus interfaces connect test software to Controller Area Network communications, helping engineers observe traffic, transmit messages, and evaluate electronic control units. Rather than measuring a sensor voltage directly, these interfaces exchange digital frames carrying operating values, commands, and diagnostic information. They support applications ranging from vehicle network development and industrial automation to hardware-in-the-loop testing and maintenance of established test systems.

The product range spans legacy NI-CAN hardware and the NI-XNET platform. Within the USB-847x family, the USB-8473, part number 779792-01, provides one high-speed CAN port and uses the NI-CAN frame API. Its monitoring features include listen-only operation and message filtering. For an existing application, retaining the correct driver family can be as important as matching the connector.

NI-XNET options include the PCI-8512 and PXI-8512, available with one or two high-speed CAN/CAN FD ports. These interfaces suit desktop expansion and modular instrumentation systems, respectively. For example, PXI-8512 part number 780687-02 provides two ports for monitoring separate CAN networks independently. Their device-driven DMA architecture reduces host processing overhead, supporting demanding frame and signal workloads. Hardware timing capabilities help engineers relate network activity to events elsewhere in a test.

For USB connectivity, the USB-8502 belongs to the USB-850x family and operates through NI-XNET. Part number 784661-01 identifies the one-port version, while 784662-01 identifies the two-port version with synchronization. USB bus power simplifies bench setups without requiring a separate interface power supply. Moving from USB-8473 hardware to USB-8502 nevertheless requires reviewing application compatibility rather than assuming an unchanged software installation will work.

C Series choices bring CAN communications into compatible CompactDAQ and CompactRIO systems. The NI-9862, part number 781639-01, offers one high-speed CAN/CAN FD port. The NI-9860, part number 783703-01, provides two hardware-selectable network ports using external transceiver cables. For high-speed CAN/CAN FD, a TRC-8542 cable supplies the required transceiver. Both modules require appropriate external power; confirm chassis, controller, and driver support before installation.

Protocol selection deserves equal attention. Classical CAN carries up to eight data bytes per frame, while CAN FD supports payloads up to 64 bytes and an optional faster data phase. Low-speed, fault-tolerant CAN is a different physical-layer requirement and should not be treated as interchangeable with high-speed CAN. Cable layout, termination, and bit timing must match the intended network. High-speed networks normally require one 120-ohm termination resistor at each physical bus end.

NI-XNET supports frame-based communication and signal-based workflows using network databases such as DBC files. Correct definitions translate message bits into meaningful engineering values. When requesting NI CAN bus interfaces from Apex Waves, provide the model, part number, port count, software environment, and network requirements to help identify an appropriate replacement or expansion option.