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====== Turn On LED Using a Button ======
<color #db5f0b>Jul 2026</color>
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{{ :micro-python.png?100 |}}
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===== Introduction =====
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In this example, we are going to turn on and off an LED on our Raspberry Pi Pico using a button. The button is a PTT (Press to Talk) style button. In this example the LED will flash slowly while the button is not pressed and quickly while the button is pressed.
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==== Add an LED and Button to the Pico ====

The image below shows what we are trying to achieve. 
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{{ :corporate:button-led-pico-003.png?500 |}}

In this example, we have the LED being connected to GP14 (pin 19) and GND (pin 18) via a 100 ohm resistor. You can use one of the GND pins on the Pico, or a common GND rail if you have made one.
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Remember, the Anode of the LED (the longer leg) goes to GP14 and Cathode goes to GND.
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The button is wired between pins GP16 (pin 21) and GND (pin 23)
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=== Micro Python Code ===

Here is the code that we will use:
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<code:python | download>
# Hardware Test
# Blink and LED (GP14) slowly/quickly while a button (GP16) is not-pressed/pressed

from machine import Pin          # Import Pin class to control GPIO pins
from time import sleep_ms        # Import millisecond sleep function

led = Pin(14, Pin.OUT)           # Create an output pin on GPIO14 for the LED
button = Pin(16, Pin.IN, Pin.PULL_UP)  # Create an input pin on GPIO16 with internal pull‑up resistor

while True:                      # Infinite loop
    if button.value() == 0:      # If button is pressed (input pulled LOW)
        delay = 100              # Use short delay (fast blink)
    else:                        # Otherwise (button not pressed)
        delay = 1000             # Use long delay (slow blink)

    led.toggle()                 # Flip LED state: ON → OFF or OFF → ON
    sleep_ms(delay)              # Wait for the chosen delay before next toggle
</code>

Because the button uses <color #00a2e8>Pin.PULL_UP</color>, its normal (unpressed) state is HIGH (1).
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Pressing the button pulls the pin to LOW (0), which is why the code checks <color #00a2e8>button.value() == 0</color>.
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{{ :corporate:button-led-pico-004.mp4?480x360 |}}

Looking at the simulation above, we can see that when the button is not pressed, we get a delay of 1000mS as per the MicroPython code, so 1 flash every two seconds (1s on, 1s off).
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When the button is pressed, we get a delay of only 100mS, so 5 flashes every second (100mS on, 100mS off x 5).
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If you have connected the LED and Button to your Pico correctly, this is what you should observe when you run the code on your setup.
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