https://devzone.nordicsemi.com/f/nordic-q-a/29344/nrf52840-usb-audioHi everyone, I am currently trying to implement USB headset on nrf52840. As far as I can see the audio example from SDK14 uses SyncType=None meaning that bmAttributes bits for an endpoint sync type set to 0. And in example description it says thaten-USTelligent Community 13Fri, 19 Jan 2018 12:38:40 GMThttps://devzone.nordicsemi.com/thread/116737?ContentTypeID=1Fri, 19 Jan 2018 12:38:40 GMT137ad170-7792-4731-bb38-c0d22fbe4515:11e64de8-4c79-4b95-90e2-622d8ed21079MartinBL<p>Unfortunately not.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/116733?ContentTypeID=1Wed, 17 Jan 2018 18:12:16 GMT137ad170-7792-4731-bb38-c0d22fbe4515:355bc5a7-2ec1-4bc9-ba8e-a62613e014b8VoidGreen<p>Then it looks like it is not possible to achieve for example 44100 or 48000 sampling rate on NRF52 I2S?</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/116736?ContentTypeID=1Mon, 15 Jan 2018 16:50:16 GMT137ad170-7792-4731-bb38-c0d22fbe4515:9369da61-a94e-48e1-aac9-71670f678775MartinBL<p>Unfortunately only 32MHz crystals work on the nRF52 family.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/116734?ContentTypeID=1Mon, 15 Jan 2018 09:41:02 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c24c261f-1c0f-4195-bdf6-e80eeeb26718VoidGreen<p>Hi thank you for your reply,</p> <p>May I use 24.756Mhz crystal on nrf52? This will give at least precise sampling rates.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/116735?ContentTypeID=1Mon, 15 Jan 2018 07:50:09 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e2b2e292-fdc2-418d-bc78-6bff0bff6f2fMartinBL<p>Hi,</p> <p>I&#39;m not sure if I understand what you want. Regarding our I2S - You are right in that there are not trimming registers and there is not much you can configure to control MCK frequency. There is only one register (MCKFREQ) that specifies how 32 MHz clock should be divided to produce MCK. And you have a set of fixed values to choose from. The next related register is RATIO which specifies how MCK (i.e. master clock) is divided to produce LRCK (i.e. left-right or sample clock – it’s frequency must correspond to the audio sample rate). And here again, you have a set of values to choose from. And that’s it, you configure these two registers to achieve desired frequency (or actually a one closest to this desired one. See <a href="http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52840.ps/pwm.html?cp=2_0_0_45_4#topic">table 97 in nRF52840_OPS_v0.5.1</a>)</p><div style="clear:both;"></div>