https://devzone.nordicsemi.com/f/nordic-q-a/20923/regards-compatibilities-of-demo-code-in-different-sdkAs a small team, we have to find silicons from retell market. Sometimes even the trader can not promise its source and batch. Here is a small list of nRF51822 available from the market. nRF51822-QFAAC0-1311AH nRF51822-QFAAC0-1322AY nRF51822-QFABA0en-USTelligent Community 13Thu, 30 Mar 2017 04:46:52 GMThttps://devzone.nordicsemi.com/thread/81726?ContentTypeID=1Thu, 30 Mar 2017 04:46:52 GMT137ad170-7792-4731-bb38-c0d22fbe4515:ae2ed9c0-4a6b-4e77-a0b4-9c95175a21f4allankliu<p>Thanks for your comments. Saving time and money.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/81727?ContentTypeID=1Wed, 29 Mar 2017 12:47:18 GMT137ad170-7792-4731-bb38-c0d22fbe4515:31935643-ecf1-4825-ba5e-b6e6e3ecf86eWojtek<p>According to <a href="http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf51/dita/nrf51/compatibility_matrix/nRF51422_nRF51822_ic_rev_sdk_sd_comp_matrix.html?cp=3_0_4">compatibility matrix</a> it is highly not recommended to use new softdevces/SDKs on old chips. You can ofc use old chips and old SD, and old SDK, but... is it really worth it? Soon, rev 1 chips will completely be gone, and you will have to move to new ones anyway. new SD and SDK provides bugfixes etc, also chips have hardware improvements. You do what you must, but I really recommend going rev. 3.</p> <p>There are some workarounds (not recommended in production) to use new SD on rev.2 chips, but using on rev.1 is not possible afaik.</p><div style="clear:both;"></div>