# ItsyBitsy 32u4 - 3V Interrupt Question

**URL:** <https://forum.arduino.cc/t/itsybitsy-32u4-3v-interrupt-question/1280250>\
**Category:** Programming\
**Created:** [July 10, 2024, 1:46pm UTC](https://forum.arduino.cc/t/itsybitsy-32u4-3v-interrupt-question/1280250 "2024-07-10T13:46:59Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![RocketNut](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/rocketnut/32/240875_2.png) [@RocketNut](https://forum.arduino.cc/u/RocketNut)\
**Post date:** [July 10, 2024, 1:46pm UTC](https://forum.arduino.cc/t/itsybitsy-32u4-3v-interrupt-question/1280250/1 "2024-07-10T13:46:59Z")

</div>

I need to do an interrupt when GPIO 15 goes high.

```cpp
#include "PinChangeInterrupt.h"

```

```cpp
attachInterrupt(digitalPinToInterrupt(15), Abort_Dect, RISING);

```

The code does not work, so what am I going wrong?

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<div class="post-metadata">

**Author:** ![gfvalvo](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/gfvalvo/32/1013044_2.png) [@gfvalvo](https://forum.arduino.cc/u/gfvalvo)\
**Post date:** [July 10, 2024, 1:50pm UTC](https://forum.arduino.cc/t/itsybitsy-32u4-3v-interrupt-question/1280250/2 "2024-07-10T13:50:55Z")

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> [@RocketNut](#):
>
> so what am I going wrong?

1. You didn't post a complete code.
2. You didn't say what the code was supposed to do.
3. You didn't say what the code actually did.

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<div class="post-metadata">

**Author:** ![blh64](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/blh64/32/605986_2.png) [@blh64](https://forum.arduino.cc/u/blh64)\
**Post date:** [July 10, 2024, 4:05pm UTC](https://forum.arduino.cc/t/itsybitsy-32u4-3v-interrupt-question/1280250/3 "2024-07-10T16:05:22Z")

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according to the docs: [https://docs.arduino.cc/language-reference/en/functions/external-interrupts/attachInterrupt/](https://docs.arduino.cc/language-reference/en/functions/external-interrupts/attachInterrupt/)

you can use pins 0,1,2,3,7 (Leonardo line in the docs since it uses the 32u4)

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<div class="post-metadata">

**Author:** ![oqibidipo](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/oqibidipo/32/221794_2.png) [@oqibidipo](https://forum.arduino.cc/u/oqibidipo)\
**Post date:** [July 10, 2024, 6:31pm UTC](https://forum.arduino.cc/t/itsybitsy-32u4-3v-interrupt-question/1280250/4 "2024-07-10T18:31:16Z")

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You are including `PinChangeInterrupt.h` but not using it.

```arduino
attachPinChangeInterrupt(digitalPinToPinChangeInterrupt(15), Abort_Dect, RISING);

```

---

<div class="post-metadata">

**Author:** ![RocketNut](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/rocketnut/32/240875_2.png) [@RocketNut](https://forum.arduino.cc/u/RocketNut)\
**Post date:** [July 10, 2024, 6:48pm UTC](https://forum.arduino.cc/t/itsybitsy-32u4-3v-interrupt-question/1280250/5 "2024-07-10T18:48:24Z")

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Thanks oqibidipo I will try your suggested code shortly.

Thank you for sharing your wisdom.

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<div class="post-metadata">

**Author:** ![RocketNut](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/rocketnut/32/240875_2.png) [@RocketNut](https://forum.arduino.cc/u/RocketNut)\
**Post date:** [July 11, 2024, 5:36pm UTC](https://forum.arduino.cc/t/itsybitsy-32u4-3v-interrupt-question/1280250/6 "2024-07-11T17:36:33Z")

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One more question if I may. Is there a way to check if the interrupt is enabled using the `PinChangeInterrupt` library?

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<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:** [January 7, 2025, 5:36pm UTC](https://forum.arduino.cc/t/itsybitsy-32u4-3v-interrupt-question/1280250/7 "2025-01-07T17:36:48Z")

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Closed on January 7, 2025, 5:36pm UTC

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