Skip to content
JEJunior Engineer LabPico W + micro:bit course
08micro:bit · MakeCode 25 minutes

External button

Read a pushbutton on P1 with an explicit pull-up.

External button project
Illustration of the finished idea. Build from the diagram and connection table, not the photo.

Lesson goal: Read P1 as a digital input with a pull-up resistor and light the P0 LED while the button is held.

Open MakeCode

Section 1

Understand

  • digital input
  • pull-up resistor
  • active low
  • if/else
  • 1A button between P1 and GND, with pull-up switched on.
  • 2Pressed reads 0, released reads 1.
  • 3The LED on P0 follows the button.

Safety first

  • Unplug the USB cable before you add, move or remove any wire. Plug back in only after an adult or you have re-checked every connection against the table.
  • micro:bit pins are 3 V logic. Never connect 5 V, a battery pack or anything from a 5 V supply to any ring, port or the 3V ring.
  • The button connects P1 to GND only. Never wire a button between 3V and GND.