diff --git a/esp-32/main.py b/esp-32/main.py
new file mode 100644
index 0000000..45c80c9
--- /dev/null
+++ b/esp-32/main.py
@@ -0,0 +1,149 @@
+import time
+import machine
+import network
+
+# ---------------------------------------------------------------------------
+# CONFIG 
+# ---------------------------------------------------------------------------
+CONFIG = {
+    # Wi-Fi du poste de test
+    "WIFI_SSID": "",
+    "WIFI_PASSWORD": "",
+
+    # Identité de dispositif (doit exister côté backend)
+    "DEVICE_ID": "esp32-01",
+    "DEVICE_SECRET": "demo-secret-esp32-01",
+
+    "BACKEND_URL": "",
+
+    # Capteur
+    "LDR_GPIO": 34,          
+
+    # Test sans envoi : True affiche le payload, n'envoie rien
+    "DRY_RUN": False,
+
+    # Rythme d'envoi en secondes
+    "SEND_INTERVAL": 3,
+}
+
+# ---------------------------------------------------------------------------
+# Lecture capteur (LDR sur GPIO34)
+# ---------------------------------------------------------------------------
+def read_ldr():
+    """Retourne la valeur brute de la LDR (0..4095, ADC 12 bits)."""
+    pin = machine.Pin(CONFIG["LDR_GPIO"], machine.Pin.IN)
+    adc = machine.ADC(pin)
+    return adc.read_u16() >> 4
+
+# ---------------------------------------------------------------------------
+# Payload JSON minimal 
+# ---------------------------------------------------------------------------
+def build_payload(raw_value):
+    """Timestamp ISO local au format de base (MicroPython n'a pas datetime)."""
+    y, m, d, hh, mm, ss, _, _ = time.localtime()
+    ts = "{:04d}-{:02d}-{:02d}T{:02d}:{:02d}:{:02d}".format(y, m, d, hh, mm, ss)
+    return {
+        "device_id": CONFIG["DEVICE_ID"],
+        "timestamp": ts,
+        "light_value": int(raw_value),
+    }
+
+# ---------------------------------------------------------------------------
+# Envoi HTTP/HTTPS 
+# ---------------------------------------------------------------------------
+def send_measure(payload):
+    import urequests  # fourni par la plupart des firmwares MicroPython
+
+    headers = {
+        "Content-Type": "application/json",
+        "X-Device-ID": CONFIG["DEVICE_ID"],
+        "X-Device-Secret": CONFIG["DEVICE_SECRET"],
+    }
+    try:
+        resp = urequests.post(CONFIG["BACKEND_URL"], json=payload, headers=headers)
+        status = resp.status_code
+        resp.close()
+        print("[send] device={} status={} ok={}".format(
+            CONFIG["DEVICE_ID"], status, 200 <= status < 300))
+        return status, (200 <= status < 300)
+    except OSError as exc:
+        # Erreur réseau : le errno aide à comprendre (voir debug ci-dessous).
+        errno = exc.args[0] if exc.args else None
+        print("[http] OSError envoi (device={}) errno={}".format(
+            CONFIG["DEVICE_ID"], errno))
+        _print_debug_network()
+        _print_debug_url()
+        return None, False
+    except Exception as exc:
+        print("[http] erreur envoi (device={}) : {}".format(
+            CONFIG["DEVICE_ID"], type(exc).__name__))
+        return None, False
+
+def _print_debug_network():
+    """Affiche l'IP que l'ESP32 a reçue + l'état Wi-Fi (debug)."""
+    try:
+        import network
+        wlan = network.WLAN(network.STA_IF)
+        if wlan.isconnected():
+            ip = wlan.ifconfig()[0]
+            print("[http]  IP locale de l'ESP32 :", ip)
+        else:
+            print("[http]  Wi-Fi NON connecté — l'envoi ne peut pas aboutir")
+    except Exception:
+        print("[http]  état Wi-Fi indisponible")
+
+
+def _print_debug_url():
+    """Affiche la cible et aide à diagnostiquer l'OSError."""
+    url = CONFIG["BACKEND_URL"]
+    print("[http]  URL cible :", url)
+    print("[http]  Astuces :")
+    print("[http]   - OSError negatif (~ -2 / -202) -> probleme DNS : "
+          "preferer une IP (192.168.x.y) a un nom d'hote")
+    print("[http]   - errno ~ -3 / 111 (refus) -> backend injoignable : "
+          "verifier IP/port du PC, backend sur 0.0.0.0, firewall")
+    print("[http]   - Rappel : 127.0.0.1 = l'ESP32 lui-meme, pas votre PC")
+
+
+# ---------------------------------------------------------------------------
+# Wi-Fi
+# ---------------------------------------------------------------------------
+def connect_wifi():
+    if not CONFIG["WIFI_SSID"]:
+        print("[wifi] SSID vide, on continue en local")
+        return False
+    wlan = network.WLAN(network.STA_IF)
+    wlan.active(True)
+    if not wlan.isconnected():
+        wlan.connect(CONFIG["WIFI_SSID"], CONFIG["WIFI_PASSWORD"])
+        for _ in range(20):
+            if wlan.isconnected():
+                break
+            time.sleep(0.5)
+    if wlan.isconnected():
+        print("[wifi] connecté, IP :", wlan.ifconfig()[0])
+    else:
+        print("[wifi] échec de connexion")
+    return wlan.isconnected()
+
+
+# ---------------------------------------------------------------------------
+# Boucle principale
+# ---------------------------------------------------------------------------
+def main():
+    connect_wifi()
+
+    if CONFIG["DRY_RUN"]:
+        print("[dry-run] payload :", build_payload(read_ldr()))
+        return
+
+    while True:
+        raw = read_ldr()
+        payload = build_payload(raw)
+        send_measure(payload)
+        time.sleep(CONFIG["SEND_INTERVAL"])
+
+
+if __name__ == "__main__":
+    main()
+