I have generated STM32CubeMX and STM32CubeIDE projects with the help of MC SDK.Referring to user manual, I connected the board to PC with USB and didn't use ST-LINK (I wonder whether it's OK). I don't know how to download the MC program to the board...
I did connected the board to PC with USB2.0 cable, and I suuplied 24V DC to the board(STEVAL-SPIN3204) and set the baudrate to 9600 bps, still this problem happens.
I'm using version 5.4.8, and I chose Keil MDK-ARM V5 as the target Toolchain. When I build the project,I also encountered error L6406E but I don't know how to deal with it.