when i connect my board with openSDA, then open freeMaster tool, boautrate is 115200, when click next step, it happeened the following error, pls help me， only connect board and pc with USB line (openSDA)
it looks, that you want to connect via UART instead of the OpenSDA. For connection via UART, you need have the running Freemaster in the board too.
If you want to use only OpenSDA, please select the highlited option in wizard.
And after then, you will see options of the debug connections: