We are facing problem with USART in STM32L475RCT7 microcontroller. Recently we have migrated an existing product from MCU stm32f103rct7 family to STM32L475RCT7.
All code changes are done properly and migration was successful. The product communicates with other hardware(xx) through USART over RS485 cable. The communication works fine for two days.
But after sometime our product (which is migrated with new MCU) did not respond to the other hardware (xx). The RS485 sniff shows that the xx hardware sends message to our product. But its clear that our product is not responding. This happens after running the communication for many hours.
We did check the systick and priority of the USART used for RS485 communication. Everything looks fine. Unfortunately the issue occurs only at our customer site. We are unable to recreate the issue in our lab. The other USART ( actually there are three, our product uses only two of them) with lowest priority than the problematic USART works fine.
Are there any known problems with STM32L475RCT7 in USART peripheral driver ?
Note:The USART is interrupt driven. We dont uses DMA or code generated by cubemx tool.
I just created a debug firmware to dump all the register info to check the software sets (RXNEIE and TXEIE) like flags and others properly or not.
Should I need to track down any other register to get more information?
Please share your suggestions.
It is evident that the Transmission Complete interrupt is not generated by the MCU and caused the receiver to be in disables state. The TCIE flag is enabled and TXE bit is set after writing all the bits in TDR register. The communication works fine for sometime, but sooner the TC interrupt doesnot happen.
