https://devzone.nordicsemi.com/f/nordic-q-a/9534/nrf51-bootloader-without-softdevice-sdk-8-1-0Hi, I want to have a bootloader without softdevice on SDK 8.1.0 I do not want to change the SDK and it seems to me the SDK only works with softdevice. Do you have such example or notes how to do it? Ranen-USTelligent Community 13Fri, 02 Oct 2015 11:12:39 GMThttps://devzone.nordicsemi.com/thread/35236?ContentTypeID=1Fri, 02 Oct 2015 11:12:39 GMT137ad170-7792-4731-bb38-c0d22fbe4515:75192389-081b-4d50-8bcb-e25e8e6c14a3Hung Bui<p>Hi Ran,</p> <p>You can have a look <a href="https://devzone.nordicsemi.com/question/33621/how-to-make-the-nrf51822-flash-jump-successful-without-softdevice/?answer=33678#post-id-33678">here</a>.</p> <p>We made an UART bootloader worked without softdevice quite long ago (SDK v4.x). The bootloader only support updating application (because there is no softdevice to update) and it&#39;s pretty old, made from SDK v4.x However, you should be able to use it with the current chip without problem. You may want to modify the configuration in project setting to match with the RAM of your chip if you are using 32kB RAM variant.</p> <p>Besides, <a href="https://devzone.nordicsemi.com/question/36214/writing-an-spi-bootloader-for-nrf51822-no-softdevice-in-bl/">here</a> is also a good explanation from RK.</p><div style="clear:both;"></div>