https://devzone.nordicsemi.com/f/nordic-q-a/11882/pca10040---uart-softdeviceHi, SDK: v11.0.0.2-alpha DK: PCA10040 (NRF52) I am trying to build a peripheral application that communicates with an external device via UART (h/w flow disabled). For this, I am using the &quot;ble_peripheral/experimental_ble_app_blink&quot; and &quot;peripheralen-USTelligent Community 13Tue, 16 Feb 2016 09:05:26 GMThttps://devzone.nordicsemi.com/thread/45004?ContentTypeID=1Tue, 16 Feb 2016 09:05:26 GMT137ad170-7792-4731-bb38-c0d22fbe4515:aa6ef648-242a-42f6-81f8-ed571ee31ef2MartinBL<p>What files and drivers are you using in your examples? There were made some changes in the uart modules in one of the latest SDKs and maybe your projects use different modules. The uart libraries are now using the nrf_drv_uart drivers. <a href="https://devzone.nordicsemi.com/question/59646/uart-sdk-migration-810-1000/">Relevant thread</a>. The <em>ble_peripheral/experimental_ble_app_blinky</em> example with these files and with this code worked for me:</p> <p><img src="https://devzone.nordicsemi.com/cfs-file/__key/communityserver-discussions-components-files/4/3617.uart.png" alt="image description" /></p> <p>Paths to files:</p> <p>SDK_11.0.0\components\libraries\fifo\app_fifo.c</p> <p>SDK_11.0.0\components\libraries\uart\app_uart_fifo.c</p> <p>SDK_11.0.0\components\drivers_nrf\uart\nrf_drv_uart.c</p><div style="clear:both;"></div>