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Topic: DHT22 not detected with ESP826 demos d1 mini (Read 107 times) previous topic - next topic

seaurchin

Sep 29, 2019, 04:29 pm Last Edit: Sep 29, 2019, 05:06 pm by seaurchin
I had a DHT22 sensor that was working with Raspberry pi zero  and Particle Photon but now I have connected to Wemos D1 Mini and looking at Serial Monitor it doesnt seems to get detected connected to Wemos D1 Mini.

a very basic code I am using to push data to thingspeak , it gets connected to internet .



Code: [Select]
#include <DHT.h>
#include <ESP8266WiFi.h>
 
// replace with your channel's thingspeak API key and your SSID and password
String apiKey = "APIKEYISHERE";
const char* ssid = "HOMESSID";
const char* password = "PASSWORDD6C";
const char* server = "api.thingspeak.com";
 
#define DHTPIN D6
#define DHTTYPE DHT22
 
DHT dht(DHTPIN, DHTTYPE);
WiFiClient client;
 
void setup()
{
Serial.begin(115200);
delay(10);
dht.begin();
 
WiFi.begin(ssid, password);
 
Serial.println();
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
 
WiFi.begin(ssid, password);
 
while (WiFi.status() != WL_CONNECTED)
{
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
 
}
 
void loop()
{
 
float h = dht.readHumidity();
float t = dht.readTemperature();
if (isnan(h) || isnan(t))
{
Serial.println("Failed to read from DHT sensor!");
return;
}
 
if (client.connect(server,80)) {
String postStr = apiKey;
postStr +="&field1=";
postStr += String(t);
postStr +="&field2=";
postStr += String(h);
postStr += "\r\n\r\n";
 
client.print("POST /update HTTP/1.1\n");
client.print("Host: api.thingspeak.com\n");
client.print("Connection: close\n");
client.print("X-THINGSPEAKAPIKEY: "+ apiKey +"\n");
client.print("Content-Type: application/x-www-form-urlencoded\n");
client.print("Content-Length: ");
client.print(postStr.length());
client.print("\n\n");
client.print(postStr);
 
Serial.print("Temperature: ");
Serial.print(t);
Serial.print(" degrees Celsius Humidity: ");



Code: [Select]
Serial.print(h);
Serial.println("Sending data to Thingspeak");
}
client.stop();
 
Serial.println("Waiting 20 secs");
// thingspeak needs at least a 15 sec delay between updates
// 20 seconds to be safe
delay(20000);
}




I have also tried solution discussed in this link: https://forum.arduino.cc/index.php?topic=510908.0
by adding 3rd flag to dht object creation.
please help .. :/

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