2-Port, USB, RS485/RS422 Serial Interface Device—The USB‑485/2 interface transforms your USB port into a single asynchronous serial port for communication with RS485 and RS422 devices. You can use a USB‑485/2 port as a standard serial port from your application, including RTS/CTS hardware handshake lines. NI serial interfaces also appear as standard COM ports for compatibility with programs that use serial communications.