https://devzone.nordicsemi.com/f/nordic-q-a/40708/cr95hf-doesn-t-respond-to-anti-collisionI have an nRF52 DK and a CR95HF development board from Mikroe ( https://www.mikroe.com/rfid-click) and I&#39;m using the Nordic SPI SDK version 14.2.0 I have managed to get the device to communicate with the CR95HF and got through the calibration phaseen-USTelligent Community 13Wed, 21 Nov 2018 20:09:46 GMThttps://devzone.nordicsemi.com/thread/158504?ContentTypeID=1Wed, 21 Nov 2018 20:09:46 GMT137ad170-7792-4731-bb38-c0d22fbe4515:67d200de-6332-4d5c-9ead-43ed37e9264fKenneth<p>My suggestion is to get a logic analyzer trace&nbsp;to find the cause (e.g.&nbsp;<a href="https://www.saleae.com/">https://www.saleae.com/</a>)&nbsp;</p> <p>The problem might anything before you can view the actual physical serial pins (order of bytes, number of bytes, pin level, speed, timing..)</p> <p>Best regards,<br />Kenneth</p><div style="clear:both;"></div>