# Arduino Nano 33 BLE Sense Pin Config and External PDM Clock

**URL:** <https://forum.arduino.cc/t/arduino-nano-33-ble-sense-pin-config-and-external-pdm-clock/1073655>\
**Category:** Nano 33 BLE Sense\
**Created:** [January 5, 2023, 3:55pm UTC](https://forum.arduino.cc/t/arduino-nano-33-ble-sense-pin-config-and-external-pdm-clock/1073655 "2023-01-05T15:55:16Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![newguy2023](https://avatars.discourse-cdn.com/v4/letter/n/e68b1a/32.png) [@newguy2023](https://forum.arduino.cc/u/newguy2023)\
**Post date:** [January 5, 2023, 3:55pm UTC](https://forum.arduino.cc/t/arduino-nano-33-ble-sense-pin-config-and-external-pdm-clock/1073655/1 "2023-01-05T15:55:16Z")

</div>

Hello Arduino!  
I need help with my small project. I was successfully able to run the [PicovoiceExample](https://github.com/Picovoice/picovoice-arduino-en) on my arduino nano 33 BLE sense. Now I want to reassign the pins to an external pdm audio stream. So bascially instead of using a PDM input from the builtin microphone on the Arduino Nano 33 BLE Sense board, I want to input an audio stream (PDM) from an external source (a microcontroller). The clock will also be refenced from the external source. How can I reassign the pins and also make my clock line to be input to the Arduino nano 33 BLE Sense?

Thanks a lot for any help!

---

<div class="post-metadata">

**Author:** ![Klaus\_K](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/klaus_k/32/626942_2.png) [@Klaus\_K](https://forum.arduino.cc/u/Klaus_K)\
**Post date:** [January 7, 2023, 1:38am UTC](https://forum.arduino.cc/t/arduino-nano-33-ble-sense-pin-config-and-external-pdm-clock/1073655/2 "2023-01-07T01:38:35Z")

</div>

Welcome to the forum.

The pins seem to be set in the following files.

- variant.cpp
- pins\_arduino.h

Both files are in the following location on my system. I have not updated it for quite a while and use the old IDE, so you will check the path on your system.

C:\Users\UserName\AppData\Local\Arduino15\packages\arduino\hardware\mbed\1.3.2\variants\ARDUINO\_NANO33BLE

There may be restrictions caused by other pin configuration code. You will have to try and use the nRF52840 datasheet as reference. Start in chapter: 6.15 PDM — Pulse density modulation interface.

---

<div class="post-metadata">

**Author:** ![system](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/system/32/1140315_2.png) [@system](https://forum.arduino.cc/u/system)\
**Post date:** [July 6, 2023, 1:39am UTC](https://forum.arduino.cc/t/arduino-nano-33-ble-sense-pin-config-and-external-pdm-clock/1073655/3 "2023-07-06T01:39:34Z")

</div>

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.