ESP8266 Community Forum

- Mon Dec 09, 2019 4:31 am #84863 I have this code and I use:

Code: Select allSerial.printf ("Docking stations =% d \ n", WiFi.softAPgetStationNum ());

To know how many devices are connected to the access point, it will not return to zero after the client is disconnected
But if the PC is connected and then disconnected, it can detect it and print zero

AP:

Code: Select all#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
#include <ArduinoJson.h>


#define led0 4                //D2


DynamicJsonBuffer jsonBuffer;

const char *ssid      = "ssid";
const char *password  = "password";

int sensorValue0 = 0;       
       
String sensor_values;

ESP8266WebServer server(80);

 WiFiClient client;
void handleSentVar() {
 
  if (server.hasArg("sensor_reading"))
  {
    sensor_values = server.arg("sensor_reading");
    Serial.print("**********************sensorValue:");
    Serial.println(sensor_values);
  }
  JsonObject& root = jsonBuffer.parseObject(sensor_values);

      sensorValue0          = root["sensor0_reading"].as<int>();
       jsonBuffer.clear();


  Serial.print("sensorValue0:");
  Serial.println(sensorValue0);


  toggle_leds();

  server.send(200, "text/html", "Data received");
}


void setup() {
  Serial.begin(9600);
  WiFi.softAP(ssid, password);
  IPAddress myIP = WiFi.softAPIP();

  pinMode(led0, OUTPUT);


 
  //toggle_leds();                 //turn off all leds as all the sensor values are zero
 
  server.on("/data/", HTTP_GET, handleSentVar); // when the server receives a request with /data/ in the string //then run the handleSentVar function
  server.begin();

 
}

void loop() {
  server.handleClient();
  Serial.printf("Stations connected = %d\n", WiFi.softAPgetStationNum());
  delay(1000);
}

void toggle_leds()
{
  if (sensorValue0 == 0){  digitalWrite(led0, LOW);
   Serial.println("++++++++++++++++off+++++++++++++");}


  if (sensorValue0 == 1){  digitalWrite(led0, HIGH);
  Serial.println("------------on-------------");}

}

Client:

Code: Select all#include <ESP8266WiFi.h>


#define btn0   5   //D1

const char *ssid = "ssid";
const char *password = "password";


int sensorValue0 = 0;       //sensor value, I'm usingg 0/1 button state

void setup() {
  Serial.begin(9600);
  delay(10);

  pinMode(btn0, INPUT);

  // set the ESP8266 to be a WiFi-client
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
  }

}

void loop() {
  Serial.print("btn");
  Serial.println(digitalRead(btn0));
if(digitalRead(btn0) == LOW) sensorValue0 = 1;
if(digitalRead(btn0) == HIGH) sensorValue0 = 0;



  // Use WiFiClient class to create TCP connections
  WiFiClient client;
  const char * host = "192.168.4.1";            //default IP address
  const int httpPort = 80;

  if (!client.connect(host, httpPort)) {
    Serial.println("connection failed");
    return;
  }

  // We now create a URI for the request. Something like /data/?sensor_reading=123
  String url = "/data/";
  url += "?sensor_reading=";
  url +=  "{\"sensor0_reading\":\"sensor0_value\"}";
  url.replace("sensor0_value", String(sensorValue0));


  // This will send the request to the server
  client.print(String("GET ") + url + " HTTP/1.1\r\n" +
               "Host: " + host + "\r\n" +
               "Connection: close\r\n\r\n");
  unsigned long timeout = millis();
  while (client.available() == 0) {
    if (millis() - timeout > 5000) {
      Serial.println(">>> Client Timeout !");
      client.stop();
      return;
    }
  }
}

Where is the problem?