Skip to content

Button Print Test

In this lab we will be testing if the three buttons have been wired up correctly. When we press any of the three buttons we will see the event printed on the Thonny console.

By printing to the console this lab is not dependant on the display being connected. In the next lab we will also modify the lab to display the button state on the display.

Using Interrupt Request Functions

To print what button is being pressed, we will write three small python functions. We then will then have these functions run when the corresponding button is pressed by running the irq function.

Sample Code

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
from utime import sleep
from machine import Pin

# Sample Raspberry Pi Pico MicroPython three button press example

# Button Pin GPIO Configuration
BUTTON_1_PIN = 13
BUTTON_2_PIN = 14
BUTTON_3_PIN = 15

# Create 3 button objects as inputs with pullup resistors
button_1_pin = Pin(BUTTON_1_PIN, Pin.IN, Pin.PULL_UP)
button_2_pin = Pin(BUTTON_2_PIN, Pin.IN, Pin.PULL_UP)
button_3_pin = Pin(BUTTON_3_PIN, Pin.IN, Pin.PULL_UP)

# These functions gets called every time a button is pressed.
def button_1_pressed(pin):
    print('Button 1 pressed')
def button_2_pressed(pin):
    print('Button 2 pressed')
def button_3_pressed(pin):
    print('Button 3 pressed')

# now we register the button handler functions using the irq setter method for each pin
button_1_pin.irq(trigger=Pin.IRQ_FALLING, handler = button_1_pressed)
button_2_pin.irq(trigger=Pin.IRQ_FALLING, handler = button_2_pressed)
button_3_pin.irq(trigger=Pin.IRQ_FALLING, handler = button_3_pressed)

# we don't do anything in the main loop but sleep
while True:
    sleep(1)