https://devzone.nordicsemi.com/f/nordic-q-a/71724/how-to-use-the-second-uartHi Im trying connect two peripheral devices through UART The example project I used is &quot;examples/peripheral/uart&quot; But i trace the code, it seems that the driver layer has been bound to UART 0 How do I use the another UART (uart 1)? iten-USTelligent Community 13Wed, 17 Feb 2021 15:44:28 GMThttps://devzone.nordicsemi.com/thread/294921?ContentTypeID=1Wed, 17 Feb 2021 15:44:28 GMT137ad170-7792-4731-bb38-c0d22fbe4515:69e43d50-a612-47ac-90a2-2532751c3850Kenneth<p>Hi,</p> <p>Looks like the app_uart implementation have only been designed with focus of supporting 1 UART instance. The instance is hard coded in top of app_uart_fifo.c as:</p> <p>static nrf_drv_uart_t app_uart_inst = NRF_DRV_UART_INSTANCE(APP_UART_DRIVER_INSTANCE);</p> <p>where&nbsp;APP_UART_DRIVER_INSTANCE is controlled in sdk_config.h.</p> <p>I recommend to check out the libuarte driver instead:<br /><a href="https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.2/lib_libuarte.html">https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.2/lib_libuarte.html</a></p> <p>Alternatively you can use the UART driver directly:<br /><a href="https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.2/hardware_driver_uart.html">https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.2/hardware_driver_uart.html</a></p> <p>Best regards,<br />Kenneth</p><div style="clear:both;"></div>