OpenMarine
Raspberry Pi Shutdown Indicator LED - Printable Version

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+--- Thread: Raspberry Pi Shutdown Indicator LED (/showthread.php?tid=6287)

Raspberry Pi Shutdown Indicator LED - JanKoopmans - 2025-06-16

? Raspberry Pi Shutdown Indicator LED using GPIO22 (OpenPlotter + MacArthur HAT)
For those running OpenPlotter on a Raspberry Pi 5 with a MacArthur HAT:
I've added a simple but super useful status LED to one of the GPIO pins. The LED indicates whether the Pi is still running. After issuing a
Code:
sudo shutdown now
, the LED turns off — so I know it's safe to cut the main power to the boat.
✅ What it does
  • ? LED ON = Raspberry Pi is running
  • ⚫ LED OFF = Raspberry Pi has shut down cleanly → you can turn off the boat’s main power
? What you need
  • 1x green LED
  • 1x 220 Ω resistor
  • Jumper wires or Dupont cables
  • A free GPIO pin (I used GPIO22 = physical pin 15)
  • Raspberry Pi 5 with OpenPlotter and MacArthur HAT
? Wiring
Connect your LED as follows:
less
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Code:
GPIO22 (pin 15) ──[220Ω]──>|── GND (pin 6)
                          LED
  • The long leg of the LED (anode) goes to the resistor
  • The short leg (cathode) goes to ground
⚙️ Software setup with
Code:
systemd
1. Turn on the LED at boot
Create the script:
bash
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Code:
sudo nano /usr/local/bin/led_on.py
Content:
python
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Code:
#!/usr/bin/env python3
from gpiozero import LED
import time

led = LED(22)
led.on()

while True:
    time.sleep(60)
Make it executable:
bash
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Code:
sudo chmod +x /usr/local/bin/led_on.py
Create a systemd service:
bash
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Code:
sudo nano /etc/systemd/system/boot-led.service
Content:
ini
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Code:
[Unit]
Description=Turn on LED at boot
After=multi-user.target

[Service]
ExecStart=/usr/bin/python3 /usr/local/bin/led_on.py
Restart=always

[Install]
WantedBy=multi-user.target
Enable it:
bash
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Code:
sudo systemctl enable boot-led.service
sudo systemctl start boot-led.service
2. Turn off the LED during shutdown
Create the script:
bash
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Code:
sudo nano /usr/local/bin/led_off.py
Content:
python
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Code:
#!/usr/bin/env python3
from gpiozero import LED

led = LED(22)
led.off()
Make it executable:
bash
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Code:
sudo chmod +x /usr/local/bin/led_off.py
Create the shutdown service:
bash
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Code:
sudo nano /etc/systemd/system/led-off.service
Content:
ini
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Code:
[Unit]
Description=Turn off LED at shutdown
DefaultDependencies=no
Before=shutdown.target

[Service]
ExecStart=/usr/bin/python3 /usr/local/bin/led_off.py
Type=oneshot

[Install]
WantedBy=shutdown.target
Enable the shutdown service:
bash
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Code:
sudo systemctl enable led-off.service
✅ Result
Your LED now gives you clear visual feedback:
Pi State
LEDRunning
? ON
Shut down
⚫ OFF
Safe to power off?
✅ Yes, when LED is OFF

ℹ️ Notes
  • Tested on Raspberry Pi 5 + MacArthur HAT + OpenPlotter
  • GPIO22 was free in my setup (double-check your own!)
  • The LED is green, powered via GPIO with a 220 Ω resistor — safe and bright


RE: Raspberry Pi Shutdown Indicator LED - BellaX - 2025-12-31

Another way that works without any line of code: just connect the LED to the 3.3V power lane. Done.
RPi 5 and CM5 have a dedicated button input to power down the system and restart it. No code needed. It works like your pc at home.

Depending on the firmware version and RPi you maybe need to allow switching off the 3.3V lane on powerdown.

Chris