If I use a multi-port converter, how do I access each port from my software on my Windows PC?
Answer:
The Connective Peripherals multi-port USB-serial adapters offer a convenient way to connect more than one serial device to your computer. For example, the USB2-H-1004-M converter provides 4 RS232 ports using just one USB port.
Each RS232 port will appear as a separate COM port on your computer, which can be opened and used simultaneously. Each port can have its serial settings (such as Baud Rate and Flow Control) set separately by the application using it too. For example, an RS232 label printer could be using port 1 (COM 4) at 115200 Baud with RTS/CTS handshaking whilst a barcode scanner could be using port 2 (COM5) at 57600 Baud with no handshaking.
You can check the Device Manager Ports (COM & LPT) section after installing the converter to see the COM numbers assigned to each port (for example USB Serial Port (COM 4)). You can also change the assigned COM port numbers to other available numbers if required.
If you are developing your own application software, you can also open ports using the FTDI D2xx library instead of as a COM port.