The National Instruments PCI-8431/2 Serial Interface (Part Number: 778980-01) is designed for high-performance communication between devices in industrial automation settings. This dual-port RS-485/RS-422 interface supports baud rates of up to 3 Mbps and utilizes advanced DMA (Direct Memory Access) technology to enable seamless data transfers directly from the serial interface to the computer memory, minimizing CPU overhead. The integration of NI-MITE ASIC with PCI bus mastering enhances the efficiency of DMA transfers, allowing data to be processed without CPU intervention, which is crucial for handling larger volumes of data. The PCI-8431/2 features two DB-9 male connectors and has a FIFO buffer size of 128 bytes, ensuring robust data handling capabilities. With a power requirement of +5 VDC at 500 mA, the device is compact, measuring 4.2 x 5.6 inches and weighing 0.20 lb. The recommended operating temperature ranges from 0 to 55 °C, with a storage temperature range of -20 to 70 °C. Although the PCI-8431/2 has reached a mature status as announced by National Instruments, it remains available for purchase and repair through Apex Waves. Comprehensive user and maintenance manuals can be downloaded online, and inquiries for pricing should be directed to a sales representative.