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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 downloaded this library (it's at the bottom), and this is the code I'm using.

#include <dht.h>
#define pin 13
dht DHT;
void setup() {

Serial.begin(9600);
  delay(2500);
  Serial.print("DHT11 Sensor: April 8 Solar eclipse data\n\n");
  delay(1500);
}


void loop() {
  DHT.read11(pin);
    Serial.print(" ");
    Serial.print(DHT.humidity);
    Serial.print(" ");
    Serial.print(DHT.temperature);
    Serial.print(",\n");
    delay(2500);


}

The goal here is to have csv's that I can copy/paste into a .csv and import to matlab to do what I need on there.

I keep getting the title and "0.00 0.00," for the two data sets. With other libraries and borrowed code sometimes I get -999 for the datasets.

My set up

schematic

simulate this circuit – Schematic created using CircuitLab

My schematic isn't super accurate, the sensor's on the breadboard. LMK your thoughts.

jsotola
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Jayven Mason
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1 Answers1

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If you are using a standalone DHT11 sensor (Without breakout board) you will need a 1KΩ pullup-resistor between 5v and Data.

The DHT's data pin is an open collector, meaning it can only pull a wire to ground to transmit data. If that wire wasn't pulled up to begin with, it won't have anything to pull down.

If your DHT11 is on a breakout board with the 1KΩ resistor already in place, I would suspect a bad sensor...

TPoE
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