Hi there,
I am trying to build a weather station, Arduino UNO+ESP8266+DHT11, and display the data on thingspeak.com.
I copied the code from https://www.instructables.com/id/Wireless-Temperature-and-Humidity-Monitor-With-ESP/. I justified the wifi name and code according to my house.
It seems the code was successfully uploaded to the UNO, but nothing happened on thingspeak channel page.
#include<stdlib.h>
#include "DHT.h"
#define SSID "2101"//your network name
#define PASS "01597928"//your network password
#define IP "184.106.153.149" // thingspeak.com
#define DHTPIN 7 // what pin the DHT sensor is connected to
#define DHTTYPE DHT11 // Change to DHT22 if that's what you have
#define Baud_Rate 115200 //Another common value is 9600
#define GREEN_LED 3 //optional LED's for debugging
#define RED_LED 4 //optional LED's for debugging
#define DELAY_TIME 60000 //time in ms between posting data to ThingSpeak
//Can use a post also
String GET = "GET /update?key=GLPFYKKUA6YN5QW1&field1=";
String FIELD2 = "&field2=";
//if you want to add more fields this is how
//String FIELD3 = "&field3=";
bool updated;
DHT dht(DHTPIN, DHTTYPE);
//this runs once
void setup()
{
Serial.begin(Baud_Rate);
Serial.println("AT");
delay(5000);
if(Serial.find("OK")){
//connect to your wifi netowork
bool connected = connectWiFi();
if(!connected){
//failure, need to check your values and try again
Error();
}
}else{
Error();
}
//initalize DHT sensor
dht.begin();
}
//this runs over and over
void loop(){
float h = dht.readHumidity();
// Read temperature as Fahrenheit (isFahrenheit = true)
float f = dht.readTemperature(true);
// Check if any reads failed and exit early (to try again).
if (isnan(h) || isnan(f)) {
LightRed();
return;
}
//update ThingSpeak channel with new values
updated = updateTemp(String(f), String(h));
//if update succeeded light up green LED, else light up red LED
if(updated){
LightGreen();
}else{
LightRed();
}
//wait for delay time before attempting to post again
delay(DELAY_TIME);
}
bool updateTemp(String tenmpF, String humid){
//initialize your AT command string
String cmd = "AT+CIPSTART="TCP","";
//add IP address and port
cmd += IP;
cmd += "",80";
//connect
Serial.println(cmd);
delay(2000);
if(Serial.find("Error")){
return false;
}
//build GET command, ThingSpeak takes Post or Get commands for updates, I use a Get
cmd = GET;
cmd += tenmpF;
cmd += FIELD2;
cmd += humid;
//continue to add data here if you have more fields such as a light sensor
//cmd += FIELD3;
//cmd += <field 3 value>
cmd += "\r\n";
//Use AT commands to send data
Serial.print("AT+CIPSEND=");
Serial.println(cmd.length());
if(Serial.find(">")){
//send through command to update values
Serial.print(cmd);
}else{
Serial.println("AT+CIPCLOSE");
}
if(Serial.find("OK")){
//success! Your most recent values should be online.
return true;
}else{
return false;
}
}
boolean connectWiFi(){
//set ESP8266 mode with AT commands
Serial.println("AT+CWMODE=1");
delay(2000);
//build connection command
String cmd="AT+CWJAP="";
cmd+=SSID;
cmd+="","";
cmd+=PASS;
cmd+=""";
//connect to WiFi network and wait 5 seconds
Serial.println(cmd);
delay(5000);
//if connected return true, else false
if(Serial.find("OK")){
return true;
}else{
return false;
}
}
void LightGreen(){
digitalWrite(RED_LED, LOW);
digitalWrite(GREEN_LED, HIGH);
}
void LightRed(){
digitalWrite(GREEN_LED, LOW);
digitalWrite(RED_LED, HIGH);
}
//if an error has occurred alternate green and red leds
void Error(){
while(true){
LightRed();
delay(2000);
LightGreen();
delay(2000);
}
}
I did not use the resistors, because I think the voltages for DHT11 (5V) and ESP8266 (3.3V) are OK, is that the source of my problem?
