My computer has 20 ports. I am unable to use more than 2 when Trying to communicate to Plc. The port that I think it may be is 3, but I am not positive.
Bring up your PC's device manager. Here's how to do this on Windws 8:
Open Device Manager by clicking the Start button , clicking Control Panel, clicking System and Maintenance, and then clicking Device Manager. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.In that tree list should be a node labeled
Ports (COM & LPT). Expand that out. You should see a bunch of ports, along with their names (e.g. COM1, COM2, COM20, etc.). Figure out which serial port(s) you want to use within DirectSOFT and use those names within your .INI file mentioned in the other posts. If you need help with this, we need to understand more about how your serial ports are installed (combinations of any/all: cards, usb to serial cables, virtual port, multiple ports on one connector, etc.).