Hi All, my first post, I am brand new to the world of Auduino and microcontrollers, I am trying to read from a dht22 using an arduino MKR 1010, and it worked fine for one sensor, when I try to add a second one to pin 3 or 4 it gives me faulty reading, I have try swapping the sensor to make sure the second is not faulty but same behaviour, if somebody could help me understand why when I use pin 2 everything works fine but if I try with pin 3 or 4 then I dont get reading or in same rare cases I get one with lower value I would appreciate it:
if I put it in pin3 I get
Publishing message
21.70
nan
Publishing message
21.70
10.80
Publishing message
21.70
nan
Publishing message
21.70
nan
in some rare cases I get in both
here is my code:
/*
AWS IoT WiFi
This sketch securely connects to an AWS IoT using MQTT over WiFi.
It uses a private key stored in the ATECC508A and a public
certificate for SSL/TLS authetication.
It publishes a message every 5 seconds to arduino/outgoing
topic and subscribes to messages on the arduino/incoming
topic.
The circuit:
- Arduino MKR WiFi 1010 or MKR1000
The following tutorial on Arduino Project Hub can be used
to setup your AWS account and the MKR board:
https://create.arduino.cc/projecthub/132016/securely-connecting-an-arduino-mkr-wifi-1010-to-aws-iot-core-a9f365
This example code is in the public domain.
*/
#include <ArduinoBearSSL.h>
#include <ArduinoECCX08.h>
#include <ArduinoMqttClient.h>
#include <WiFiNINA.h> // change to #include <WiFi101.h> for MKR1000
#include "DHT.h"
#include "arduino_secrets.h"
/////// Enter your sensitive data in arduino_secrets.h
const char ssid[] = SECRET_SSID;
const char pass[] = SECRET_PASS;
const char broker[] = SECRET_BROKER;
const char* certificate = SECRET_CERTIFICATE;
WiFiClient wifiClient; // Used for the TCP socket connection
BearSSLClient sslClient(wifiClient); // Used for SSL/TLS connection, integrates with ECC508
MqttClient mqttClient(sslClient);
unsigned long lastMillis = 0;
//assign pins for temperature and humidity sensors 1 and 2
#define DHTPIN 2 // Digital pin 2 connected to the DHT sensor1
#define DHTPIN2 3 // Digital pin 3 connected to the DHT sensor2
// Feather HUZZAH ESP8266 note: use pins 3, 4, 5, 12, 13 or 14 --
// Pin 15 can work but DHT must be disconnected during program upload.
// Uncomment whatever type you're using!
//#define DHTTYPE DHT11 // DHT 11
#define DHTTYPE DHT22 // DHT 22 (AM2302), AM2321
//#define DHTTYPE DHT21 // DHT 21 (AM2301)
// Connect pin 1 (on the left) of the sensor to +5V
// NOTE: If using a board with 3.3V logic like an Arduino Due connect pin 1
// to 3.3V instead of 5V!
// Connect pin 2 of the sensor to whatever your DHTPIN is
// Connect pin 3 (on the right) of the sensor to GROUND (if your sensor has 3 pins)
// Connect pin 4 (on the right) of the sensor to GROUND and leave the pin 3 EMPTY (if your sensor has 4 pins)
// Connect a 10K resistor from pin 2 (data) to pin 1 (power) of the sensor
// Initialize DHT sensor.
// Note that older versions of this library took an optional third parameter to
// tweak the timings for faster processors. This parameter is no longer needed
// as the current DHT reading algorithm adjusts itself to work on faster procs.
// create multiple instances of a DHT object.
DHT dht(DHTPIN, DHTTYPE);
DHT dht2(DHTPIN2, DHTTYPE);
// 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 = 0;
// Read temperature as Celsius (the default)
float t = 0;
// Read temperature as Fahrenheit (isFahrenheit = true)
float f = 0;
//sensor2
float h2 = 0;
// Read temperature as Celsius (the default)
float t2 = 0;
// Read temperature as Fahrenheit (isFahrenheit = true)
float f2 = 0;
// exist in previous code removed this - rafa start
/*
void setup() {
Serial.begin(9600);
Serial.println(F("DHTxx test!"));
dht.begin();
}
*/
// exist in previous code will remove this rafa end
void setup() {
dht.begin();
Serial.begin(115200);
while (!Serial);
if (!ECCX08.begin()) {
Serial.println("No ECCX08 present!");
while (1);
}
// Set a callback to get the current time
// used to validate the servers certificate
ArduinoBearSSL.onGetTime(getTime);
// Set the ECCX08 slot to use for the private key
// and the accompanying public certificate for it
sslClient.setEccSlot(0, certificate);
// Optional, set the client id used for MQTT,
// each device that is connected to the broker
// must have a unique client id. The MQTTClient will generate
// a client id for you based on the millis() value if not set
//
// mqttClient.setId("clientId");
// Set the message callback, this function is
// called when the MQTTClient receives a message
mqttClient.onMessage(onMessageReceived);
}
void loop() {
if (WiFi.status() != WL_CONNECTED) {
connectWiFi();
}
//delay(2000);
// Reading temperature or humidity takes about 250 milliseconds!
// Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
h = dht.readHumidity();
// Read temperature as Celsius (the default)
t = dht.readTemperature();
// Read temperature as Fahrenheit (isFahrenheit = true)
f = dht.readTemperature(true);
//sensor2
h2 = dht2.readHumidity();
// Read temperature as Celsius (the default)
t2 = dht2.readTemperature();
// Read temperature as Fahrenheit (isFahrenheit = true)
f2 = dht2.readTemperature(true);
if (!mqttClient.connected()) {
// MQTT client is disconnected, connect
connectMQTT();
}
// poll for new MQTT messages and send keep alives
mqttClient.poll();
// publish a message roughly every 5 seconds.
if (millis() - lastMillis > 5000) {
lastMillis = millis();
publishMessage();
}
}
unsigned long getTime() {
// get the current time from the WiFi module
return WiFi.getTime();
}
void connectWiFi() {
Serial.print("Attempting to connect to SSID: ");
Serial.print(ssid);
Serial.print(" ");
while (WiFi.begin(ssid, pass) != WL_CONNECTED) {
// failed, retry
Serial.print(".");
delay(5000);
}
Serial.println();
Serial.println("You're connected to the network");
Serial.println();
}
void connectMQTT() {
Serial.print("Attempting to MQTT broker: ");
Serial.print(broker);
Serial.println(" ");
while (!mqttClient.connect(broker, 8883)) {
// failed, retry
Serial.print(".");
delay(5000);
}
Serial.println();
Serial.println("You're connected to the MQTT broker");
Serial.println();
// subscribe to a topic
mqttClient.subscribe("arduino/incoming");
}
void publishMessage() {
Serial.println("Publishing message");
// send message, the Print interface can be used to set the message contents
mqttClient.beginMessage("arduino/outgoing");
//mqttClient.print("hello ");
mqttClient.print(F("Humidity Sensor1: "));
mqttClient.print(h);
mqttClient.print(F("% Temperature Sensor1: "));
mqttClient.print(t);
Serial.println(t);
//sensor2
delay(1000);
mqttClient.print(F("Humidity Sensor2: "));
mqttClient.print(h2);
mqttClient.print(F("% Temperature Sensor2: "));
mqttClient.print(t2);
Serial.println(t2);
mqttClient.endMessage();
}
void onMessageReceived(int messageSize) {
// we received a message, print out the topic and contents
Serial.print("Received a message with topic '");
Serial.print(mqttClient.messageTopic());
Serial.print("', length ");
Serial.print(messageSize);
Serial.println(" bytes:");
// use the Stream interface to print the contents
while (mqttClient.available()) {
Serial.print((char)mqttClient.read());
}
Serial.println();
Serial.println();
}
