Serial Ports Splitter - Split COM port and use it by multiple applications simultaneously
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Create Split Serial Ports

This window allows you to create a split port configuration:

New Split Port Window

First select the device you want to split. Then press the + button to add two or more aliases for the port being split. You can also delete an added alias by selecting it in the list and pressing the - button.

Optionally, specify the port settings overrides by pressing the Options button.