A and B Buttons

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


Using A and B Buttons


Load KOI Extension: https://github.com/KittenBot/pxt-koi

Loading Extensions

Blocks for buttons:


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:


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)

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


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.