I met the problem when use the USART multiprocessor mode. In my USART communication application, even for one USART, there are 3 different addressses for different data packages. But STM32F4 only provide one address to be compared. If I don't use the multiprocessor mode, I cannot identify the data or address on the bus. The basic requirement for me is to identify the data or address on the bus and if the addresses are not for this node, it will ignore or mute. The addresses for one node not only fixed one. So how can I implement? It works different with ARM7.