The PCIe-8431/16 module is a high-performance interface for high-speed communication with RS-485 and RS-422 devices. The module offers data transfers via the high-speed DMA interface, multithreading and multiprocessor support. Users can choose between 4- and 2-wire transceiver modes for full- and half-duplex communication. NI's serial ports appear as standard COM ports, ensuring compatibility with programs that use serial communication.