stm32 to UART on the HAT UP4000

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stm32 to UART on the HAT UP4000

UP4000 with UP-APL03 R1.1 (UPAPBM11)(07/01/2022).

• Use lubuntu 18
• Bios UPAPBM11
• Installed the Upboard Kernel
• Configure support for the GPIO header (https://github.com/up-board/up-community/wiki/Ubuntu_18.04)
  But I get no returned chars on tty5.

I have many Up4000 board in my lab. So I tried to install in same condition and setup. Result is another 3 upboard can get chars from UART port.

How I can solve?