DHT22 Sensor Programming Help

Projects Programming
1

Hello, I'm trying to interface a DHT22 Temp/Humidity Sensor with an Arduino UNO. I'm trying to follow the tutorial seen at this site. Overview | DHT11, DHT22 and AM2302 Sensors | Adafruit Learning System I've tried following the examples that were provided in the library. GitHub - adafruit/DHT-sensor-library: Arduino library for DHT11, DHT22, etc Temperature & Humidity Sensors But only the character of "a" shows up in the serial monitor. I believe everything is hooked up correctly. Any help would be greatly appreciated.

2

Hi,

I am going to answer first, have not looked at the links you provided, I believe, it would be best if you supply the sketch you are using. The people(not me) here know what they are talking about and as such may look at the links you have just given and reply " works for me"

Hmm that would be the best scenario, doubt they could spare the time or trouble.

I know, seems tough, but, post your code, we all start somewhere, do not be ashamed of your code, show it.

Ian

3

You might also confirm that the serial monitor speed exactly matches that of the Arduino, as defined in the sketch.

4

This was the example I tried to use. I'm using an UNO so I believe it matches.

// Example testing sketch for various DHT humidity/temperature sensors
// Written by ladyada, public domain

#include "DHT.h"

#define DHTPIN 2 // what pin we're connected to

// Uncomment whatever type you're using!
//#define DHTTYPE DHT11 // DHT 11
#define DHTTYPE DHT22 // DHT 22 (AM2302)
//#define DHTTYPE DHT21 // DHT 21 (AM2301)

// Connect pin 1 (on the left) of the sensor to +5V
// Connect pin 2 of the sensor to whatever your DHTPIN is
// Connect pin 4 (on the right) of the sensor to GROUND
// Connect a 10K resistor from pin 2 (data) to pin 1 (power) of the sensor

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);
  Serial.println("DHTxx test!");
 
  dht.begin();
}

void loop() {
  // Reading temperature or humidity takes about 250 milliseconds!
  // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
  float h = dht.readHumidity();
  float t = dht.readTemperature();

  // check if returns are valid, if they are NaN (not a number) then something went wrong!
  if (isnan(t) || isnan(h)) {
    Serial.println("Failed to read from DHT");
  } else {
    Serial.print("Humidity: ");
    Serial.print(h);
    Serial.print(" %\t");
    Serial.print("Temperature: ");
    Serial.print(t);
    Serial.println(" *C");
  }
}
5

I'm using an UNO so I believe it matches.

Which Arduino you are using has nothing to do with the Serial Monitor speed.