# AI Fusion Lab, 2.1 Button

**URL:** https://forum.sunfounder.com/t/ai-fusion-lab-2-1-button/4525
**Category:** Learning kit for Raspberry Pi
**Created:** [April 5, 2026, 6:21pm UTC](https://forum.sunfounder.com/t/ai-fusion-lab-2-1-button/4525 "2026-04-05T18:21:12Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![paks](https://yyz1.discourse-cdn.com/flex029/user_avatar/forum.sunfounder.com/paks/32/1769_2.png) [@paks](https://forum.sunfounder.com/u/paks)
#### Post date: [April 5, 2026, 6:21pm UTC](https://forum.sunfounder.com/t/ai-fusion-lab-2-1-button/4525/1 "2026-04-05T18:21:12Z")

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Hello Again! I’m wondering why you would have us put a 10 kohms resistor as a pulldown on the button switch when you have it in this line of code : button = Pin(17, mode=Mode.IN, pull=Pull.DOWN).

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### Author: ![SunFounder\_Moderator](https://avatars.discourse-cdn.com/v4/letter/s/34f0e0/32.png) [@SunFounder\_Moderator](https://forum.sunfounder.com/u/SunFounder_Moderator)
#### Post date: [April 7, 2026, 4:00am UTC](https://forum.sunfounder.com/t/ai-fusion-lab-2-1-button/4525/2 "2026-04-07T04:00:46Z")

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That’s a great question.

In the code, pull=Pull.DOWN does enable the GPIO’s internal pull-down resistor, which is sufficient for normal button operation in most cases. Therefore, an external 10kΩ pull-down resistor is not strictly necessary.

The reason a 10kΩ pull-down resistor is included in the circuit diagram is mainly as a general hardware design practice. External resistors are typically more stable and offer better noise immunity compared to internal pull-down resistors.

You may choose either approach. We will update our documentation accordingly.