🛠 Suder le header 40 broches et faire clignoter une LED

Objectives

Solder the 40-pin header (supplied unmounted on the Zero W), then light up an LED via GPIO17 using gpiozero.

Hardware

• 1 Raspberry Pi Zero W + 2.54 mm 40-pin header (the Zero WH version comes pre-soldered)
• 1 soldering iron, solder wire, breadboard
• 1 LED + 330 Ω resistor, jumper wires

Steps

1. Place the header on the component side, aligning pin 1 with the two square pads near the USB/HDMI connectors; solder diagonally to avoid solder bridges.
2. Wiring: pin 11 = GPIO17 → 330 Ω resistor → LED anode; cathode → pin 14 = GND. The logic level is 3.3 V, with a maximum of 16 mA per pin and 50 mA total for the entire header — the Zero W has no ADC/DAC.
3. Install the library: sudo apt install python3-gpiozero, then:

from gpiozero import LED
from time import sleep
led = LED(17)   # broche physique 11
while True:
    led.toggle
    sleep(0.5)

Verification

gpioinfo (gpiod package) lists gpiochip0; the LED blinks once per second. Stop with Ctrl-C.

Common errors

• Confusing physical numbering (11) with GPIO numbering (17) — gpiozero uses GPIO numbers.
• Wiring to pins 2/4 which supply 5 V instead of 3.3 V.
• Overloading the header: beyond 50 mA cumulative, the board crashes before any protection kicks in.
• Solder bridge: check with a magnifying glass and multimeter before powering up.