https://devzone.nordicsemi.com/f/nordic-q-a/12785/nrf51822-uart-and-softdevice-enabledWe have a nrf51822 chip connected to an arduino-like device. We need to use UART for communication, but without firmware modification the master chip doesn&#39;t support USART (no default CTS and RTS pins). In the main UART example code on GIT I read,en-USTelligent Community 13Fri, 25 Mar 2016 07:59:13 GMThttps://devzone.nordicsemi.com/thread/48593?ContentTypeID=1Fri, 25 Mar 2016 07:59:13 GMT137ad170-7792-4731-bb38-c0d22fbe4515:35e140b6-dc51-4606-bd26-3994bbe07b76RK<p>No that&#39;s not the case, you can run without flow control, however your baud rate will be quite limited to ensure the constant softdevice interrupts don&#39;t cause buffer overruns.</p><div style="clear:both;"></div>