BQ24780SEVM-583: Learn mode

Part Number:BQ24780SEVM-583

Hi expert,

 I connect Vsys to a CC mode E-load and connect Vbat to a power source. When I enable the learn mode by  battery management studio. The Vsys is still equal to Vadaptor.It seem didn't go into learn mode.  After  reading register, the REG0x12[5]=0. How to enable the learn mode in EVM?