https://devzone.nordicsemi.com/f/nordic-q-a/1600/esb-on-nrf51822Hello, I have two nRF24L01 devices that can already talk to each other on a custom address. When I try to talk to the nRF51822 from one of the nRF24L01 devices, I cannot get the ESB library to work. I am working off of the example code provided in theen-USTelligent Community 13Sun, 21 Dec 2014 10:55:54 GMThttps://devzone.nordicsemi.com/thread/7066?ContentTypeID=1Sun, 21 Dec 2014 10:55:54 GMT137ad170-7792-4731-bb38-c0d22fbe4515:4e2662b7-80c2-4f15-8cfa-fb98bda21d6fMartin<p>Fixed 404 link. <a href="https://devzone.nordicsemi.com/documentation/nrf51/5.2.0/html/a00139.html#esb_backwards">devzone.nordicsemi.com/.../a00139.html</a></p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/7065?ContentTypeID=1Mon, 17 Feb 2014 13:08:57 GMT137ad170-7792-4731-bb38-c0d22fbe4515:489a93b3-b134-44e7-b404-f9f2a82477acH&#229;kon Alseth<p>Hi Adam,</p> <p>In order to get backwards compatibility, there are a couple of registers that needs to be set on the nRF24L01+ side. If you&#39;re using the hal_nrf-library, the calls can be found here: <a href="https://devzone.nordicsemi.com/documentation/nrf51/5.1.0/html/a00139.html#esb_backwards">devzone.nordicsemi.com/.../a00139.html</a></p> <p>Most likely, you are not using that library, so here&#39;s the registers that needs to be set:</p> <ul> <li>EN_DPL</li> <li>EN_DYN_ACK</li> <li>EN_ACK_PAY</li> <li>the corresponding fields in DYNPD</li> </ul> <p>If you still have any issues, please post the code for both nRF24 and nRF51 side.</p> <p>Best regards Håkon</p><div style="clear:both;"></div>