Resolved! Documentation: USART1/2 and APB2/1 on STM32U5 series
Is USART1 on APB1 (AN5593, tab.17) or APB2 (DS, RM, CubeMX) and USART2 on APB1 (DS, RM, CubeMX) or APB2 (AN5593, tab.17)? Guess, there is an issue in an5593-how-to-use-the-gpdma-for-stm32u5-series-microcontrollers-stmicroelectronics Rv.4 , isn‘t it?