https://devzone.nordicsemi.com/f/nordic-q-a/70910/softdevice-v4-0-2-does-not-send-att-write-responseI am using a nRF52832 custom board based on SDK11 and SD 4.0.2 configured as a peripheral with a GATT server. I am seeing a case where the client is an Iphone XR iOS v13.2.3 and after the phone sends an ATT Write Request, the nRF does not send an ATTen-USTelligent Community 13Tue, 26 Jan 2021 14:03:59 GMThttps://devzone.nordicsemi.com/thread/291304?ContentTypeID=1Tue, 26 Jan 2021 14:03:59 GMT137ad170-7792-4731-bb38-c0d22fbe4515:d2d6ca7e-a8d8-4880-bab8-6d764fca1cbbKenneth<p>Hi,</p> <p>I suspect either of two may be the problem here:</p> <p>1. Make sure that your system_nrf52.c file include workaround for errata_108(), please see this errata description and description on how to update the mdk files:</p> <p><a href="https://infocenter.nordicsemi.com/topic/errata_nRF52832_Rev2/ERR/nRF52832/Rev2/latest/anomaly_832_108.html">https://infocenter.nordicsemi.com/topic/errata_nRF52832_Rev2/ERR/nRF52832/Rev2/latest/anomaly_832_108.html</a>&nbsp;<a href="https://devzone.nordicsemi.com/f/nordic-q-a/55378/mdk-uvision-sdk-16-0-keil-family-pack-installation/224413#224413"><br />https://devzone.nordicsemi.com/f/nordic-q-a/55378/mdk-uvision-sdk-16-0-keil-family-pack-installation/224413#224413</a>&nbsp;</p> <p>2. Makes use the S132 SD v4.0.5, this is drop-in compatible with the SD v4.0.2:<br /><a href="https://www.nordicsemi.com/Software-and-tools/Software/S132/Download#infotabs">https://www.nordicsemi.com/Software-and-tools/Software/S132/Download#infotabs</a>&nbsp;</p> <p>Kenneth</p><div style="clear:both;"></div>