Cannot add bi-directional pins to SignalTap-II... Should it be so?

Hello,

Is it possible to add bi-directional pins to SignalTap-II?

I'm receiving the following error message:

Error (11120): The signal hps_fbr_top:i_hps_fbr_top|hps_fbr_top_hps_0:hps_0|hps_fbr_top_hps_0_hps_io:hps_io|hps_fbr_top_hps_0_hps_io_border:border|hps_io_i2c1_inst_SCL~input between I/O input buffer, phys_impl SOC_VIO, port O, bus_index 0 and LAB, phys_impl LAB, port N/A, bus_index -1 cannot be implemented

Please advice.

Thank you!