|USB to RS-232 interface converter is intended for conversion from USB interface (USB 1.1, USB 2.0) into two independent RS-232 interfaces in duplex and half-duplex modes of data exchange.
1. Power supply.
Power supply is made from host-controller (power unit of personal computer) or from USB-hub with internal power supply 5 V.
Connection is done to host-controller (system case of personal computer) or to USB-hub through cable USB-A, mounted into case of the converter. Peripheral devices with RS-232 interfaces is connected through DB-9F connectors (female).
3. Interaction of the personal computer with USB to RS-232 interface converter.
Physical USB-port of the converter – channel of USB interface, which is connected to computer or hub. Virtual USB-ports of the converter are created in Windows OS after connection of the physical USB-port to computer and installation of the converter drivers: “USB Serial Converter A“ and “USB Serial Converter B”.
Physical COM-ports of the converter – channels of RS-232 interface, having names COM1 and COM2, to which external peripheral devices are connected. Virtual COM-ports of the converter are created in Windows OS after installation of the converter drivers. These program virtual ports correspond to physical COM-ports of the converter, which Windows OS gives names “COMx” with numbers from 1 to 256.
As a result with virtual COM-ports of the converter a software application can work as with general COM-ports and request to virtual COM from the application leads to control over physical port port of the converter.
More information: http://www.technotrade.ua/usb-to-rs-232-interface-converter.html