# A and B Buttons

KOI has 2 built in programmable buttons called A and B.

<figure><img src="https://kittenbothk.readthedocs.io/en/latest/_images/01-1.png" alt=""><figcaption></figcaption></figure>

### Using A and B Buttons

<figure><img src="https://kittenbothk-eng.readthedocs.io/en/latest/_images/mcbanner.png" alt=""><figcaption></figcaption></figure>

#### **Loading Extensions**

Search "KOI" in the search bar.

<figure><img src="https://kittenbothk.readthedocs.io/en/latest/_images/koi_search.png" alt=""><figcaption></figcaption></figure>

Or copy and paste the following link to the search bar.

**<https://github.com/KittenBot/pxt-koi>**

Blocks for buttons:

<figure><img src="https://kittenbothk-eng.readthedocs.io/en/latest/_images/02-1.png" alt=""><figcaption></figcaption></figure>

btnA and btnB refer to Button A and B respectively.

When the button is being pressed, it returns a value of 1. When it is not being pressed, it returns a value of 0.

#### Sample Program:

{% embed url="<https://makecode.microbit.org/_LMD1x65LgU2E>" %}

### Program Flow

Download the program to Micro:bit.

Pressing button A on the KOI causes Micro:bit to show a smiley face, pressing button B on the KOI causes Micro:bit to show a surprised face.

### Sample Code

[KOI AB Buttons (Extension0.5.7)](https://makecode.microbit.org/_cjVL49CmfWKJ)

### Extension Version and Updates

There may be updates to extensions periodically, please refer to the following link to update/downgrade your extension.

[Makecode Extension Update](https://kittenbothk-eng.readthedocs.io/en/latest/Makecode/makecode_extensionUpdate.html)

### FAQ

#### 1: There is no reaction after pressing the buttons on the KOI.

· A: This is because KOI has a longer boot time than Micro:bit. When the power is turned on, Micro:bit has already ran the code for KOI initialization before KOI is ready.

· Solution: Reset your Micro:bit after KOI has been turned on. (The trick is to let KOI power on completely before initialization.)

#### 2: Does KOI work with 3V input?

· A: No, KOI only works with 5V.