I have two stm32 on my board. I send serial data from stm32f407 to both max232 and stm32h743. The output data from the max232 is correct. but when I debug the stm32h743 input serial data, its data is incorrect. what is the problem?

Dear all,I want to program my STM32F407 by UART.I can connect to the microcontroller correctly by uart. boot0 is high and boot1 is low.I can read the pre-programmed code by the uart.I can erase the microcontroller.But I cannot program my stm32f407. T...