#!/usr/bin/env python3 """ Flask web UI to trigger 4 GPIO outputs on a Raspberry Pi (Bookworm/Pi 5 friendly). - Uses gpiozero (with the LGPIO backend) instead of deprecated RPi.GPIO. - 4 buttons on the homepage. Clicking a button pulses the mapped GPIO pin once. Install (Raspberry Pi OS Bookworm): sudo apt update && sudo apt install -y python3-gpiozero python3-lgpio Run: python3 app.py Then open http://:5000 NOTE: - Ensure the downstream device shares GND with the Pi and is 3.3V‑tolerant. - If the line drives a relay/coil or >3.3V logic, use a transistor/optocoupler level-shifter. """ import atexit import threading import time from typing import List from flask import Flask, render_template_string, request, redirect, url_for, jsonify from gpiozero import OutputDevice # ==================== Configuration ==================== # BCM pins for the 4 channels (matches your example) RELAY_PINS: List[int] = [14, 15, 18, 23] # Pulse duration in seconds PULSE_DURATION: float = 0.01 # Active level for your downstream device: # True -> drive pin HIGH for active pulse # False -> drive pin LOW for active pulse (open-collector style boards, or active-low inputs) ACTIVE_HIGH: bool = True # ======================================================= # Prepare OutputDevice objects. We set initial_value=False so lines idle LOW by default (adjust as needed). channels: List[OutputDevice] = [ OutputDevice(pin, active_high=True, initial_value=False) for pin in RELAY_PINS ] # Ensure cleanup on exit @atexit.register def _cleanup(): for ch in channels: try: ch.off() ch.close() except Exception: pass # Lock to prevent overlapping pulses per process pulse_lock = threading.Lock() def pulse(index: int, duration: float = PULSE_DURATION): ch = channels[index] with pulse_lock: if ACTIVE_HIGH: ch.on() time.sleep(duration) ch.off() else: # active-low pulse ch.off() # ensure idle state ch.toggle() # go active-low time.sleep(duration) ch.toggle() # return to idle app = Flask(__name__) INDEX_HTML = """ GPIO 控制面板

GPIO 控制面板

点击按钮以脉冲激活对应的 GPIO（BCM）。默认脉冲：{{ pulse_duration * 1000 | round(1) }}ms；模式：{{ 'ACTIVE_HIGH' if active_high else 'ACTIVE_LOW' }}

{% for idx, pin in enumerate(pins) %}

通道 {{ idx }}

GPIO {{ pin }}

{% endfor %}

""" @app.route("/") def index(): return render_template_string( INDEX_HTML, pins=RELAY_PINS, pulse_duration=PULSE_DURATION, active_high=ACTIVE_HIGH, enumerate=enumerate, ) @app.route("/activate/", methods=["POST"]) # form action def activate(idx: int): if idx < 0 or idx >= len(channels): return ("Invalid channel index", 400) threading.Thread(target=pulse, args=(idx,), daemon=True).start() return redirect(url_for("index")) @app.route("/api/activate", methods=["POST"]) # programmatic JSON API def api_activate(): data = request.get_json(silent=True) or {} if "index" not in data: return jsonify({"ok": False, "error": "missing 'index'"}), 400 idx = int(data["index"]) if idx < 0 or idx >= len(channels): return jsonify({"ok": False, "error": "invalid index"}), 400 threading.Thread(target=pulse, args=(idx,), daemon=True).start() return jsonify({"ok": True, "index": idx, "pin": RELAY_PINS[idx], "duration_sec": PULSE_DURATION, "active_high": ACTIVE_HIGH}) if __name__ == "__main__": app.run(host="0.0.0.0", port=5000, debug=False)