🛠 Se connecter au Wi-Fi et publier des événements cloud

Objectives

Configure the Photon's Wi-Fi (Soft AP procedure, not Smart Config as on the older Spark Core), check the connection status via the RGB LED, then publish and receive events using Particle.publish and Particle.subscribe — without writing a single line of networking code, as everything is integrated into the Device OS.

Hardware

• 1 Particle Photon (2.4 GHz Wi-Fi only: Broadcom BCM43362 802.11b/g/n chip, no 5 GHz support)
• a smartphone or computer for Soft AP configuration
• ideally a second Photon to test subscriptions

Complete Code

// photon-wifi-publish.ino — publication d'événements toutes les 10 s
unsigned long derniere = 0;

void setup {
  Serial.begin(9600);
  Particle.subscribe("door/opened", onDoor);  // événement d'un autre appareil
}

void loop {
  if (millis - derniere > 10000) {
    derniere = millis;
    bool ok = Particle.publish("salle/temperature", "21.5", PRIVATE);
    Serial.print("publish ok=");
    Serial.println(ok ? "1" : "0");
  }
  delay(50);
}

void onDoor(const char *event, const char *data) {
  Serial.print("evenement recu: ");
  Serial.print(event);
  Serial.print(" data=");
  Serial.println(data);
}

Expected Verification

After configuration (long press on SETUP, then connect to the Photon's Soft AP network and enter the Wi-Fi password), the RGB LED breathes cyan: connected to the cloud. particle subscribe my/salle/temperature displays private events. The PRIVATE flag is confirmed by the sample code in the guide.

Common Errors

• 5 GHz Router: the BCM43362 only sees 2.4 GHz, causing the Photon to get stuck.
• Publishing too fast: the cloud limits event throughput, causing publish calls to fail (returning false).
• Unstable Wi-Fi during an OTA update: users report getting stuck in magenta (no cloud connection) after a failed OTA.
• Forgetting that the old api.spark.io endpoint is closed: everything must go through api.particle.io.