National Instruments 778473-04 Serial Interface Device 

National Instruments part number 778473-04 is a 4 port Serial Interface Device, also known by the model name USB-232/4 This device is designed to integrate seamlessly with regular personal computers running Microsoft Windows. In the Windows environment, it functions like a standard hardware serial communication port. The front panel of the NI 778473-04 features LEDs that provide real-time status updates. Its sturdy casing allows it to withstand typical industrial environments where standard cable interfaces may not be durable. Known for its reliability and precision, this device can operate in either DCE or DTE mode as selected via software. Under normal operation, it draws approximately 300 mA from the host USB bus, with a peak of up to 500 mA at +5 VDC. 

Being USB-powered, it does not require a separate power cable or jack. Moreover, the 4-ports of the 778473-04 offers software-selectable DTE or DCE transceiver modes, along with an automatic transceiver detection mode known as Auto232. The device also includes software-selectable biasing, allowing users to enable or disable biasing for each port through software controls. Development environments such as Visual Basic, Visual C++, and Excel, as well as National Instruments LabVIEW, LabWindows/CVI, and Measurement Studio, support access to these serial ports using standard serial I/O functions. It is built to convert a standard USB port into four standard serial ports. 

The 778473-04 features a USB 2.0 B-type plug connector and provides access to the four serial ports via individual DB-9 male connectors. This serial Interface Device is bus-powered, meaning it draws power directly from the USB serial bus and does not require an additional power supply. It is compatible with a wide range of computer programs and applications that utilize standard COM ports.