Hi Carmine, Thanks for the excellent book. If I understand chapter 9 correctly, UART RX using DMA in interrupt mode, will interrupt after a given number of bytes received. If I don’t know how may bytes are being transferred, then I would have to set the len argument to 1 and interrupt on each byte received, and add it to an RTOS queue (or ringbuffer) that I can service when my app has time. In this use case, does using DMA provide any performance benefit over a non DMA RX interrupt?