How to determine the slot configuration is described in 38.213-11.1, but it is described in so complicated way and I think it will take long time for me to understand all the details.

My understanding at the very high level is as follows.

• First, UE determine the slot configuration based on TDD-UL-DL-ConfigurationCommon  
• If there are any flexible slots or symboles in the slot configuration within TDD-UL-DL-ConfigurationCommon, these slots / symbols can be configured as DL or UL later using TDD-UL-DL-ConfigDedicated.
• If RRC message configures about SFI related parameters(SlotFormatCombination) and UE recieves DCI 2_0, it applies the slot configuration specified in DCI 2_0.

Reference

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