NI PCI-8431/8 High-Performance Serial Interface (RS485/RS422)

The NI PCI-8431/8 is an eight-port serial interface card for RS485 and RS422 communication in industrial and automation environments. It delivers high-speed DMA transfers to reduce CPU overhead while maintaining full compatibility with standard serial communication software. The card supports operation across Windows 7/Vista/XP/2000 and LabVIEW Real-Time platforms, appearing as standard COM ports for seamless integration with existing applications.

– Technical Specifications

• Ports: 8 RS485/RS422 serial ports
• Maximum Baud Rate: 3 Mbps (3,000 kbits/s)
• Baud Rate Accuracy: 0.01% for standard rates; 1% for customizable rates up to 3,000 kbits/s
• Configurable Range: 2 baud to 3,000 kbits/s
• FIFO Buffer: 128 bytes transmit and receive
• Interface Type: Universal PCI
• Transceiver Modes: 4-wire full-duplex and 2-wire half-duplex
• Data Transfer: High-speed DMA
• I/O Connector: 68-pin SCSI with included adapter to eight DB-9 male connectors
• Power: +5 VDC at 1.3 A typical, 1.9 A maximum

– Key Features

• Hyperthreading and multiprocessor compatible
• Appears as standard COM ports for third-party application compatibility
• DMA architecture minimizes CPU load in high-throughput scenarios
• Compact form factor: 4.2 × 5.7 inches (10.67 × 14.48 cm); 85 g

– Environmental Specifications

• Operating Temperature: 0 to 55 °C
• Storage Temperature: –20 to 70 °C
• Operating Humidity: 10 to 90% noncondensing
• Storage Humidity: 5 to 95% noncondensing

– Compatibility & Integration

Operating systems: Windows 7, Vista, XP, 2000, and LabVIEW Real-Time. The card integrates into existing PCI slots and works with standard COM port drivers and serial communication libraries, eliminating custom integration overhead.