Questions tagged [dht11]
The dht11 tag has no usage guidance.
12 questions
1
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1
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DHT11 Sensor - reading either all zeros or all -999 (depending on library)
So I've been trying to get a small project set up for the upcoming eclipse, just to read changes in the humidity and temp during the eclipse.
I have two DHT11 sensors, I'm only using one.
I have ...
- 11
1
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1
answer
99
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How execution time of code instructions influences signal between Arduino and DHT11?
I am exemining code for DHT11 from CircuitGeeks, variant without using lib. The problem is a mismatch between DHT11/DHT22 protocol and signals, which are read from sensor in scetch. Despite this, ...
- 23
2
votes
1
answer
78
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DHT11's data on MAX7219 reads 0
I want print data from a DHT11 (temperature and humidity) on a MAX7219 LED display but it only shows 0. Serial monitor, on the other hand, shows both humidity and temperature which means that my ...
- 53
1
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0
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181
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dht11 data on ESP32 NTP clock (updated)
I'm trying to get my ESP32 internet clock to show temperature and humidity data from a dht11 sensor on a MAX7219 display but my code seems to have some issues. After verifying the code there are no ...
- 11
0
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1
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169
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ERROR: return reinterpret_cast<T>(pgm_read_ptr(p));
I need to update DHT sensor data to the webserver in JSON format using ESP8266. This is my code.
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#...
- 11
1
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0
answers
95
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Arduino cant send DHT11 data to Firebase
I have a problem with my project, the problem is that my Firebase can't detect my DHT11 temperature and humidity sensor from the Arduino.
The code runs without an error but the Firebase can't read my ...
- 51
1
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0
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54
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esp8266 r1 mini stops serial print during execution
The setup includes an WEMOS/ESP8266 R1 mini compatible board, a DHT11, a photo resistor and a magnetic reed.
The libs used are:
#include <ESP8266WiFi.h>
#include <PubSubClient.h>
#include &...
- 51
1
vote
1
answer
337
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DHT11 temperature and humidity sensor Code
I’ve got a question about this code I’ve attached please- would it be correct to read it like this:
After defining the variable temperature and humidity and assigning measurement_timestamp to millis(),...
- 13
0
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1
answer
627
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DHT11 stops working when power comes from a power supply board
I had a mini project with a DHT11, a temperature and humidity sensor, working perfectly on my Arduino UNO clone. Then, I bought a power supply board, that can feed the sensor with the 5V it requires, ...
- 103
0
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2
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2k
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DHT22 sensor reading code interprets negative values weirdly
The following code reads the DHT22 temperature and humidity values, assuming the pin value as the sensor's host pin.
When the temperature drops below 0°C, this code returns inadequate values in the ...
- 153
2
votes
1
answer
617
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DHT11 humidity and temperature sensor
Hello. I've got a question about DHT11 sensor. Why should pullup resistor be connected as on the image below:
while as far as I know, pullup resistor should be placed between Arduino 5V pin and Vcc ...
- 41
1
vote
1
answer
924
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Dht 11 sensors give null value
void Sensor_value()
{ server.handleClient();
humidity = dht.readHumidity();
temperature = dht.readTemperature();
}
I want to make condition if temperature = null and Humidity= null ...
