I'm using the FRDM_K66 board and running the FreeRTOS Uart Demo project. I've been able to modify it receive data from an external source and to recover from ring buffer overrun. This is my typical use case since the application will come up on a live bus that could be generating a steady stream of data and we need to obtain sync by parsing until we see the synchronization pattern. What I've observed though is that if I start the application on a quiet bus and then start the data stream I end up in the HardFault_Handler ISR. I don't see how to trace back from this though I can set breakpoints and figure it out eventually. I'm just curious since it is not clear to me what events are bound to this interrupt number. Any remarks or commentary would be helpful.