https://devzone.nordicsemi.com/f/nordic-q-a/45197/how-to-send-string-data-from-nrf51-to-nrf-52-with-bleHello ! I encountered a problem in sending and receiving data from one nrf51 card to another nrf52 card i use this method in (ble_config.c) to send string data : void send_string(char * string_to_send) { ble_nus_string_send(&amp;m_nus, (uint8_t *) string_to_senden-USTelligent Community 13Thu, 21 Mar 2019 14:43:09 GMThttps://devzone.nordicsemi.com/thread/177634?ContentTypeID=1Thu, 21 Mar 2019 14:43:09 GMT137ad170-7792-4731-bb38-c0d22fbe4515:fbb38224-d5f5-4d1f-b4dc-8900d3413694awneil[quote userid="77986" url="~/f/nordic-q-a/45197/how-to-send-string-data-from-nrf51-to-nrf-52-with-ble"] I encountered a problem[/quote] <p><strong><em>What</em> problem</strong>, exactly, did you encounter?</p> <p></p> <p>How to properly post source code:</p> <p><img alt=" " src="https://devzone.nordicsemi.com/resized-image/__size/320x240/__key/communityserver-discussions-components-files/4/7446._5F00_Insert-Code-_2D00_-Nordic.png" /></p><div style="clear:both;"></div>