I am trying to recreate the same project
http://forum.arduino.cc/index.php?PHPSESSID=0lm0o7rko0ei3p4pdqjid12662&topic=232640.0
The objective is same to have the temperature / humidity be transmitted wirelessly using DHT11 sensor and be read through Serial Monitor of the computer.
When I compile the TX code below. I get the error message ----
"DHT11" was not declared in this scope.
Which DHT library did you use? Is there a link to download it? I am using DHT11 sensor too.
Any help would be appreciated.
#include <SPI.h>
#include <nRF24L01p.h>
#include "DHT.h"
#define DHTPIN 2 // what pin we're connected to
#define DHTTYPE DHT11 // DHT 11 (AM2302)
DHT dht(DHTPIN, DHTTYPE);
nRF24L01p transmitter(7,8);//CSN,CE
String message;
String error = "Failed to read from DHT";
void setup(){
delay(150);
Serial.begin(115200); //Initializing Serial communication Arduino<====>PC
Serial.println("DHTxx test!");
dht.begin();//DHT sensor Initializing
SPI.begin();// Initializing SPI
SPI.setBitOrder(MSBFIRST);// set the transmission as MSB First
transmitter.channel(90);
transmitter.TXaddress("Artur");
transmitter.init(); // Initializing transmitter
}
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();//store Humidity reading
float t = dht.readTemperature();//store Temperature reading
// check if returns are valid, if they are NaN (not a number) then something went wrong!
if (isnan(t) || isnan(h)) {
transmitter.txPL(error); // If no sensor is present send this acknowledgement message
transmitter.send(SLOW); //
Serial.println("Failed to read from DHT");// For debugging
}
else {
// create a String containing the required data
message = "Humidity: " + String(h) + " %\t" + "Temperature: " + String(t) + " *C";
Serial.println (message); // for debugging
transmitter.txPL(message);
transmitter.send(SLOW);
message=""; // empty the message String
}
}