does any one here experienced with various dht11 library for arduino?, I want to read the temperature value every 30 second, I am using the standard library but sometimes throw me NaN. In avarege I got 2 NaN values out of 10 readings (20%).
I got many errors about many dht11 libraries, but one day finally I found a good library and good example code.
Firstly you have to download the library from this link and add this to arduino's library folder.
Secondly, you should do this pin connections
Lastly, here it is example code. It should work.
#include <dht11.h>
int DHT11_pin=2;
dht11 DHT11_sensor;
void setup()
{
Serial.begin(9600);
Serial.println("GOOD LUCK");
Serial.println("*********************");
}
void loop()
{
int chk = DHT11_sensor.read(DHT11_pin);
Serial.print("Humidity (%): ");
Serial.println((float)DHT11_sensor.humidity, 2);
Serial.print("Temp (Celcius): ");
Serial.println((float)DHT11_sensor.temperature);
Serial.print("Temp (Kelvin): ");
Serial.println(DHT11_sensor.kelvin(), 2);
Serial.print("Temp (Fahrenheit): ");
Serial.println(DHT11_sensor.fahrenheit(), 2);
Serial.print("Dew Point: ");
Serial.println(DHT11_sensor.dewPoint(), 2);
Serial.println("------------------");
delay(500);
}
Related
I have an MD02 sensor (SHT20). In the storefront it says that this sensor is part of the MD02 series and not the XY-MD02.
But the store description says it can be configured according to the XY-MD02 register. After I tried, the register couldn't be used on the modbus poll. I used the register datasheet on the web http://www.sah.rs/media/sah/techdocs/xy-md02-manual.pdf
I also tried to read Modbus using HW0519 and ESP32, but the result is still the same. The register does not issue any output.
My Code:
#define RXD2 16
#define TXD2 17
byte ByteArray[250];
int ByteData[20];
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
Serial2.begin(9600, SERIAL_8N1, RXD2, TXD2);
}
void loop() {
// put your main code here, to run repeatedly:
delay(1000);
byte msg[] = {0x01,0x04,0x00,0x01,0x00,0x01,0x60,0x0A};
int i;
int len=8;
Serial.println("Sending Data...");
for(i=0 ; i < len ; i++){
Serial2.write(msg[i]);
Serial.print("[");
Serial.print(i);
Serial.print("]");
Serial.print("=");
Serial.print(String(msg[i],HEX));
}
len = 0;
Serial.println();
Serial.println();
int a = 0;
while(Serial2.available()){
ByteArray[a] = Serial2.read();
a++;
}
int b = 0;
String Register;
Serial.println("Receiving Data...");
for(b=0;b<a;b++){
Serial.print("[");
Serial.print(b);
Serial.print("]");
Serial.print("=");
Register = String(ByteArray[b],HEX);
Serial.print(Register);
Serial.print(" ");
}
Serial.println();
Serial.println();
}
I've made sure the wiring diagram is correct. How to fix it? I'm very confused, because there are no relevant solutions on the internet.
i have same problem. But, i solved this.
The solution
Change your modbus poll with odd/even parity. I swear that the description is wrong.
That the result if changing your parity
Temp/Hum have 100 Resolution, just divide by 100.
Change your code using SERIAL_8E1 or SERIAL_8O1
The code:
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
Serial2.begin(9600, SERIAL_8E1, RXD2, TXD2);
}
Have a nice day!!!
Although the manufacturer claimed the device worked on 9600 8N1 - my device only worked on 9600 8N2 (or 8X1 + any parity check). In addition, a large timeout for waiting for a response is required (in my case, a stable response was only with a timeout of 1000 ms or more).
I am facing a total weird problem one set of code is running and other ain't.
This code is working:
int pin = 2;
void setup() {
// put your setup code here, to run once:
pinMode(pin, OUTPUT);
digitalWrite(pin, LOW);
}
void loop() {
// put your main code here, to run repeatedly:
}
And at the same time this is not working:
int pin = 2;
void setup() {
// put your setup code here, to run once:
pinMode(pin, OUTPUT);
digitalWrite(pin, LOW);
}
void loop() {
// put your main code here, to run repeatedly:
digitalWrite(pin,HIGH);
delay(5000);
digitalWrite(pin,LOW);
delay(5000);
}
Try putting an LED on your D2 pin to check whether it lights up or not. Make sure to add a resistor (220 ohm or 330 ohm) before the LED. Also, LED has polarity. The small leg should be towards the ground and the long leg (anode) should be towards the D2 pin.
If you don't have an LED or resistor, try using Serial.print() to display whether the system is going through your code or not. You can view your serial response through your serial monitor.
I am trying to read data from both the sensor and the gps (one by one is ok). The sensors work well individually but the Ultrasonic sensor does not give any output. I am new to arduino so i just mixed the codes from the two examples using NewPing Library and TinyGPS libraries. Here is the code. Please suggest what additions need to be made to the code to make both devices work together.
/*********************
*10 to GPS Module TX*
*09 to GPS Module RX*
*********************/
// 1.TESTED USING LED
// 2. added ultrasound libraries
#include <NewPing.h>
#define TRIGGER_PIN 5 // Arduino pin tied to trigger pin on the ultrasonic sensor.
#define ECHO_PIN 4 // Arduino pin tied to echo pin on the ultrasonic sensor.
#define MAX_DISTANCE 400 // Maximum distance we want to ping for (in centimeters). Maximum sensor distance is rated at 400-500cm.
NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE); // NewPing setup of pins and maximum distance.
#include <SoftwareSerial.h>
#include <TinyGPS.h>
SoftwareSerial mySerial(10, 11);
TinyGPS gps;
float gpsdump(TinyGPS &gps);
void setup()
{
// Oploen serial communications and wait for port to open:
Serial.begin(9600);
// set the data rate for the SoftwareSerial port
mySerial.begin(9600);
delay(1000);
}
void loop() // run over and over
{
bool newdata = false;
unsigned long start = millis();
// Every 5 seconds we print an update
while (millis() - start < 5000)
{
if (mySerial.available())
{
char c = mySerial.read();
//Serial.print(c); // uncomment to see raw GPS data
if (gps.encode(c))
{
newdata = true;
break; // uncomment to print new data immediately!
}
}
}
if (newdata)
{
Serial.println("Acquired Data");
Serial.println("-------------");
gpsdump(gps);
Serial.println("-------------");
Serial.println();
}
}
float gpsdump(TinyGPS &gps)
{
// On Arduino, GPS characters may be lost during lengthy Serial.print()
// On Teensy, Serial prints to USB, which has large output buffering and
// runs very fast, so it's not necessary to worry about missing 4800
// baud GPS characters.
Serial.println("speed");
Serial.println(gps.f_speed_kmph()) ;
Serial.print(sonar.ping_cm());
;
}
The main problems:
You cannot wait 5 seconds without processing the characters. The Arduino receive buffer only has room for 64 characters. The GPS device could have sent 5000 characters during that time, so most of them will get dropped. This prevents the GPS library from ever parsing a complete sentence.
A ping will interfere with software serial ports. You will have to wait for the GPS quiet time to do the ping. Otherwise, the ping process will cause characters to be lost.
Other problems:
You are printing the speed value even though it may not be valid. If you are not moving, or you do not have good satellite reception, the GPS device may not provide a speed.
The Arduino millis() clock will not be synchronized with the GPS clock. You could use the GPS updates as an exact 1-second clock. Simply count 5 fixes as they arrive, and this will mean that 5 seconds have elapsed.
You should use a different serial port and/or library.
This answer describes the various choices: HardwareSerial (i.e. Serial on pins 0 & 1), AltSoftSerial (8 & 9 on an UNO) or NeoSWSerial (any two pins).
Here is a NeoGPS version of your sketch that addresses these issues:
/*********************
*10 to GPS Module TX*
*09 to GPS Module RX*
*********************/
// 1.TESTED USING LED
// 2. added ultrasound libraries
#include <NewPing.h>
#define TRIGGER_PIN 5 // Arduino pin tied to trigger pin on the ultrasonic sensor.
#define ECHO_PIN 4 // Arduino pin tied to echo pin on the ultrasonic sensor.
#define MAX_DISTANCE 400 // Maximum distance we want to ping for (in centimeters). Maximum sensor distance is rated at 400-500cm.
NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE); // NewPing setup of pins and maximum distance.
#include <NeoSWSerial.h>
#include <NMEAGPS.h>
NeoSWSerial gpsPort(10, 11);
NMEAGPS gps; // the parser
gps_fix fix; // all the parsed values from GPS
uint8_t fixCount = 0; // a one-second "clock"
float gpsdump();
void setup()
{
// Open serial communications and wait for port to open:
Serial.begin(9600);
// set the data rate for the SoftwareSerial port
gpsPort.begin(9600);
delay(1000);
}
void loop() // run over and over
{
// Check for available GPS characters and parse them
if (gps.available( gpsPort ))
{
// Once per second, a complete fix structure is ready.
fix = gps.read();
fixCount++;
// The GPS device is going to be quiet for a while,
// *now* is a good time to do a ping.
Serial.print( "ping " );
Serial.println( sonar.ping_cm() );
// Every 5 seconds we print an update
if (fixCount >= 5)
{
fixCount = 0; // reset counter
Serial.println("Acquired Data");
Serial.println("-------------");
gpsdump();
Serial.println("-------------");
Serial.println();
}
}
}
float gpsdump()
{
// On Arduino, GPS characters may be lost during lengthy Serial.print()
// On Teensy, Serial prints to USB, which has large output buffering and
// runs very fast, so it's not necessary to worry about missing 4800
// baud GPS characters.
Serial.println("speed ");
if (fix.valid.speed)
Serial.println( fix.speed_kph() );
}
If you want to try it, NeoGPS, AltSoftSerial and NeoSWSerial are available from the IDE Library Manager, under the menu Sketch -> Include Library -> Manage Libraries. NeoGPS is smaller, faster, more reliable and more accurate than all other libraries.
Even if you don't use it, there are many suggestions on the Installation and Troubleshooting pages.
I am trying to create a basic arduino uno stopwatch displayed on a liquid crystal display. In theory , this is a very easy project, yet I am running into issues with my display. I calculate my minutes and seconds, and then attempt to print them to the display with a colon in between. Coming from java, I presumed a plus was just used. However, this results in a bunch of random, unidentifiable characters flashing on the screen. I tested to see if both seconds and minutes work separate, which they do, so I think it is in the syntax of lcd.print(). I was not able to find this addressed anywhere else. Help would be appreciated.
Code:
#include <LiquidCrystal.h>
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
int seconds;
int minutes;
int timedif;
int starttime = -1;
void setup()
{
lcd.begin(16, 2); //Initialize the 16x2 LCD
lcd.clear(); //Clear any old data displayed on the LCD
}
void loop()
{
lcd.setCursor(0,0);
lcd.print("Stopwatch");
lcd.setCursor(0,1);
if (starttime == -1) { //if running first time, time dif is initiated
starttime = millis();
}
timedif = (millis() - starttime)/1000; //will get difference in terms of seconds
minutes = floor(timedif/60); // divides by sixty, drops decimal
seconds = timedif%60; //gets remainder of divided by 60
lcd.print(minutes + ";" + seconds);
}
What you are printing is a JAVA syntax , and Arduino is using C syntax.
See this on how you need to use this API.
You need to build the string (for example as char array) and passed it to the print method
code dose not perfect work
int pushButton = 2;
int gearstatus = 0 ;
int buttonState;
void setup() {
Serial.begin(9600);
pinMode(pushButton, INPUT);
}
void gearfunction(){
buttonState = digitalRead(pushButton);
while(gearstatus <= 5){
Serial.println( gearstatus);
if(buttonState == HIGH){
gearstatus++;}
}
}
void loop() {
gearfunction();
}
in this code i am trying to if statement in while loop,
but code doesn't work . can some one give me how to did this ? i want to increase gearstatus up to 5 but value not increase .
It doesn't work because marking pushButton as INPUT wont make it equal to HIGH
You need to put inside setup function after the input instruction:
digitalWrite(pushButton,HIGH)
A Button-Pin has to be initialized on Setup, like in the preceding answer or with:
pinMode(2, INPUT_PULLUP); //Pin-D2. This command activates it's internal
//resistor, so the resulting signal is clear HIGH and not floating like a duck...
Hint: on StartUp all pins of a uC are floating-inputs, so if pulled-UP
they may be grounded with a button or anything else like a sensor, NTC-Resistor, etc.), resulting in a clear "1" or "0" - or a defined Analog-Signal, which later may be scanned like:
boolean buttonState = digitalRead(2); //Pin D2
//or
int value = analogRead(A0); //Pin A0
Can you please explain a little what you are trying to do, It would be better if you attach a small image of the circuit. I can suggest you the code and answer using circuits.io if you give the required info.