I am stucked in my “home sensor” project and I have tried every single possibilites I can think of. I will tear my hair of soon because I cannot understand what Im doing wrong.
Hardware:
Wemos D1 Mini
DHT 11 Sensor (This is the easy one that everybody can do but now Im stucked with it)
BH1750 Lightsensor
DS18B20 Temperature Sensor
Below is my code for all this and every sensor works but not the DHT11 !?
I have tried the DHT11 sensor with the scetchbuilder and the same wiring as I have now and then it works.
But when I try my own code, it will not work !
Please help me ! Im sure it is simple for an experianced coder out there but for me as a beginner, its not. I also hope this can help someone else.
So here is the code
#define BLYNK_PRINT Serial // Comment this out to disable prints and save space
#define ONE_WIRE_BUS 14 // DS18B20 Data wire is plugged into port 14 on the Wemos D1mini
#define DHTPIN 2 // What digital pin we're connected to
#define DHTTYPE DHT11 // DHT 11
#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>
#include <SimpleTimer.h>
#include <Wire.h>
#include <BH1750.h>
#include <DallasTemperature.h>
#include <DHT.h>
OneWire oneWire(ONE_WIRE_BUS); // Setup a oneWire instance to communicate with any OneWire devices (not just Maxim/Dallas temperature ICs)
DallasTemperature sensors(&oneWire); // Pass our oneWire reference to Dallas Temperature.
BH1750 lightMeter;
DHT dht(DHTPIN, DHTTYPE);
char auth[] = "-----------------------";
char ssid[] = "-----------------------";
char pass[] = "----------------------";
SimpleTimer timer;
float outsideTemperature; //Outside Temperature in Celsius
/********************************************************************************************/
void sendUptime(){
uint16_t lux = lightMeter.readLightLevel();
Blynk.virtualWrite(V5, lux);
sensors.requestTemperatures(); // Send the command to get temperatures
outsideTemperature = sensors.getTempCByIndex(0); // Stores temperature. Change to getTempCByIndex(0) for celcius.
Blynk.virtualWrite(V4, outsideTemperature); // Send temperature to Blynk app virtual pin.
float h = dht.readHumidity();
float t = dht.readTemperature(); // or dht.readTemperature(true) for Fahrenheit
if (isnan(h) || isnan(t)) {
Serial.println("Failed to read from DHT sensor!");
return;
}
// You can send any value at any time.
// Please don't send more that 10 values per second.
Blynk.virtualWrite(V7, h);
Blynk.virtualWrite(V6, t);
}
void setup(){
Serial.begin(9600);
Blynk.begin(auth, ssid, pass);
// Initialize the I2C bus (BH1750 library doesn't do this automatically)
Wire.begin();
// On esp8266 you can select SCL and SDA pins using Wire.begin(D4, D3);
lightMeter.begin();
sensors.begin(); // Start up the library for DS18B20
dht.begin();
timer.setInterval(1000L, sendUptime); // Temperature sensor read interval. 2000 (ms) = 2 seconds.
}
void loop() {
Blynk.run();
timer.run();
}
@PeteKnight Thank you for your thoughts and tips but unfortunately they did not help me.
I changed the timer to diffrent values 5s, 6s, 7s etc. but it did not make any diffrence.
As for the GPIO pin, first of all I use a Wemos D1 Mini and not a NodeMCU for this but thats okay.
The GPIO pin works with the blynk example code wich I will show you down here. Same wiring, same GPIO. It works with the example code from blynk scetch builder but not with my program abowe.
So I still dont know what to do. I hope someone can help me.
Here is the example code from Blynk Scetch Builder and that code works just fine:
/* Comment this out to disable prints and save space */
#define BLYNK_PRINT Serial
#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>
#include <DHT.h>
// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth[] = "---------------";
// Your WiFi credentials.
// Set password to "" for open networks.
char ssid[] = "-----------------";
char pass[] = "----------------";
#define DHTPIN 2 // What digital pin we're connected to
// Uncomment whatever type you're using!
#define DHTTYPE DHT11 // DHT 11
//#define DHTTYPE DHT22 // DHT 22, AM2302, AM2321
//#define DHTTYPE DHT21 // DHT 21, AM2301
DHT dht(DHTPIN, DHTTYPE);
BlynkTimer timer;
// This function sends Arduino's up time every second to Virtual Pin (5).
// In the app, Widget's reading frequency should be set to PUSH. This means
// that you define how often to send data to Blynk App.
void sendSensor()
{
float h = dht.readHumidity();
float t = dht.readTemperature(); // or dht.readTemperature(true) for Fahrenheit
if (isnan(h) || isnan(t)) {
Serial.println("Failed to read from DHT sensor!");
return;
}
// You can send any value at any time.
// Please don't send more that 10 values per second.
Blynk.virtualWrite(V7, h);
Blynk.virtualWrite(V6, t);
}
void setup()
{
// Debug console
Serial.begin(9600);
Blynk.begin(auth, ssid, pass);
dht.begin();
// Setup a function to be called every second
timer.setInterval(1000L, sendSensor);
}
void loop()
{
Blynk.run();
timer.run();
}
Sorry, I didn’t see that you said it was a Wemos D1 Mini that you are using, but exactly the same comments apply as with the NodeMCU.
Your screenshots shows a humidity reading of 17% and an indoor temperature of 24°. These numbers are coming from the DHT11, so exactly what isn’t working?
@PeteKnight Yes you are right, my screenshots shows values but when I touch the sensor or blow at it or even put it outside it doesent change values at all.
It stays at 17% Humidity and 24°C indoor whatever I do.
@PeteKnight Yes it is. In my program but not in the program from Blynk Schetch Builder.
Looking at these two programs right now. I printed them out on a paper to sit down and try to figure this out. It makes me kind of frustrated because I know it should work, something in the code is not correct for sure but because Im a newbie its a learning process and it takes time.
So I changed my code a little bit. I set up a new void and put the dht in that void alone as you can see. It now works but I still get errors in serial monitor sometimes “Failed to read from DHT”. Very often accualy but I read in another post that another guy had the same problem.
At least it works now, but as I said not without problems so if anyone can help, I would be more then happy
Niklas
New Code:
#define BLYNK_PRINT Serial // Comment this out to disable prints and save space
#define ONE_WIRE_BUS 14 // DS18B20 Data wire is plugged into port 14 on the Wemos D1mini
#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>
#include <SimpleTimer.h>
#include <Wire.h>
#include <BH1750.h>
#include <DallasTemperature.h>
#include <DHT.h>
OneWire oneWire(ONE_WIRE_BUS); // Setup a oneWire instance to communicate with any OneWire devices (not just Maxim/Dallas temperature ICs)
DallasTemperature sensors(&oneWire); // Pass our oneWire reference to Dallas Temperature.
BH1750 lightMeter;
char auth[] = "";
char ssid[] = "";
char pass[] = "";
#define DHTPIN 13 // What digital pin we're connected to
#define DHTTYPE DHT11 // DHT 11
DHT dht(DHTPIN, DHTTYPE);
SimpleTimer timer;
float outsideTemperature; //Outside Temperature in Celsius
/********************************************************************************************/
void sendUpdht(){
float h = dht.readHumidity();
float t = dht.readTemperature(); // or dht.readTemperature(true) for Fahrenheit
if (isnan(h) || isnan(t)) {
Serial.println("Failed to read from DHT sensor!");
return;
}
// You can send any value at any time.
// Please don't send more that 10 values per second.
Blynk.virtualWrite(V6, t);
Blynk.virtualWrite(V7, h);
}
void sendUptime(){
sensors.requestTemperatures(); // Send the command to get temperatures
outsideTemperature = sensors.getTempCByIndex(0); // Stores temperature. Change to getTempCByIndex(0) for celcius.
Blynk.virtualWrite(V4, outsideTemperature); // Send temperature to Blynk app virtual pin.
uint16_t lux = lightMeter.readLightLevel();
Blynk.virtualWrite(V5, lux);
}
void setup(){
Serial.begin(9600);
Blynk.begin(auth, ssid, pass);
// Initialize the I2C bus (BH1750 library doesn't do this automatically)
Wire.begin();
// On esp8266 you can select SCL and SDA pins using Wire.begin(D4, D3);
lightMeter.begin();
sensors.begin(); // Start up the library for DS18B20
dht.begin();
timer.setInterval(1000L, sendUpdht); // Temperature sensor read interval. 2000 (ms) = 2 seconds.
timer.setInterval(1000L, sendUptime); // Temperature sensor read interval. 2000 (ms) = 2 seconds.
}
void loop() {
Blynk.run();
timer.run();
}
