https://devzone.nordicsemi.com/f/nordic-q-a/55230/app_uart-called-during-an-interruption-not-working-properlyDear community, I am developing a firmware using SDK 16.0.0 which handles interruptions from an accelerometer and a timer. I&#39;ve built on top of APP_UART lib a set of functions for printing to the console as well as WifI module. After configuringen-USTelligent Community 13Fri, 06 Dec 2019 11:08:22 GMThttps://devzone.nordicsemi.com/thread/224134?ContentTypeID=1Fri, 06 Dec 2019 11:08:22 GMT137ad170-7792-4731-bb38-c0d22fbe4515:057674ba-46e9-4477-a2fb-fe82672a52b0Susheel Nuguru<p>Excellent :)</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/224133?ContentTypeID=1Fri, 06 Dec 2019 10:58:07 GMT137ad170-7792-4731-bb38-c0d22fbe4515:7f9b3c13-c528-459a-840a-467b62088b64Ricardo Vicente<p>Hi!<br /><br />Well this is silly but as you&#39;ve mentioned FIFO it just ringed a bell!<br /><br />I&#39;ve changed the IRQ priority level on UART in the sdk config, BUT the FIFO macro has an argument where you pass the priority as well.</p> <p><pre class="ui-code" data-mode="text">APP_UART_FIFO_INIT(param, UART_RX_BUF_SIZE, UART_TX_BUF_SIZE, _uart_error_handle, APP_IRQ_PRIORITY_LOWEST, err_code);</pre></p> <p>I&#39;ve changed APP_IRQ_PRIORITY_LOWEST to APP_IRQ_PRIORITY_HIGH and it is working now.<br /><br />Thank you!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/223896?ContentTypeID=1Thu, 05 Dec 2019 12:40:19 GMT137ad170-7792-4731-bb38-c0d22fbe4515:098c5e20-47e1-46ef-ae0c-fa414ebfa0bbSusheel Nuguru<p>I think I have seen this behavior before. I think it was related to adding wrong fifo file into the project. Can you give me a list of all FIFO and uart related file names in your project?</p><div style="clear:both;"></div>