https://devzone.nordicsemi.com/f/nordic-q-a/25596/timeslot-esb-prx-becomes-stuck-soon-after-ptx-keeps-sending-messageHi, PTX: based on the SDK11 &quot;\examples\proprietary_rf\esb_ptx\pca10040\blank\arm4\esb_ptx_blank_pca10040.uvproj&quot;, what I changed is delete the &quot;nrf_delay_us(50000)&quot; in main(), to make it sends ESB message more quickly. PRX: based on the codeen-USTelligent Community 13Mon, 09 Oct 2017 08:55:40 GMThttps://devzone.nordicsemi.com/thread/100895?ContentTypeID=1Mon, 09 Oct 2017 08:55:40 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c6060262-9e01-47dc-ade8-4c2f0c283df3XiongYin<p>Hi Hung Bui,</p> <p>It works now, the issue doesn&#39;t occur in about half an hour. I&#39;ll keep testing to see if it works too when running for long time.</p> <p>Thank you!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/100894?ContentTypeID=1Mon, 02 Oct 2017 12:41:25 GMT137ad170-7792-4731-bb38-c0d22fbe4515:1c6c76fd-82f1-4734-adad-5c9406ce9004Hung Bui<p>Hi XiongYin,</p> <p>Thanks for the detailed information and the demo code.</p> <p>We found that it was due to a bug in the implementation of nrf_esb.c</p> <p>So if you in nrf_esb_stop_rx() modify :</p> <pre><code>if (m_nrf_esb_mainstate == NRF_ESB_STATE_PRX) </code></pre> <p>to</p> <pre><code> if ((m_nrf_esb_mainstate == NRF_ESB_STATE_PRX)||(m_nrf_esb_mainstate ==NRF_ESB_STATE_PRX_SEND_ACK)) </code></pre> <p>It should work. Please let me know if the issue still occurs.</p><div style="clear:both;"></div>