What I am trying to do is to read the value pulseIn(ECHO, HIGH), so that I eventually can convert it to centimeters, so I know how far the ultrasonic sensor is from an object. However when I read the value printed in the Serial Monitor it is only 3 or 4 and it is with no regard to how far the ultrasonic sensor is from anything. I can't even see why it would be exactly these two values or why it changes between them. I cannot figure how to solve this problem or what can cause it. I don't know whether the problem is with the code or components. However, this sensor was recently tested by someone else and it worked then, so maybe it is just me who is doing something wrong. Help?
#define SPEAKER 11
#define TRIGGER 2
#define ECHO 3
#define SPLIT 40
unsigned long duration;
int alarm1()
{
Serial.print("alarmtest");
analogWrite(SPEAKER, 100);
delay(100);
analogWrite(SPEAKER, 0);
delay(100);
analogWrite(SPEAKER, 100);
delay(100);
analogWrite(SPEAKER, 0);
delay(500);
}
void setup()
{
Serial.begin(9600);
pinMode(SPEAKER, OUTPUT);
pinMode(TRIGGER, OUTPUT);
pinMode(ECHO, INPUT);
}
void loop()
{
digitalWrite(TRIGGER, LOW);
delayMicroseconds(50);
digitalWrite(TRIGGER, HIGH);
delayMicroseconds(50);
digitalWrite(TRIGGER, LOW);
duration = pulseIn(ECHO, HIGH);
delay(200);
Serial.print(duration);
if (duration < SPLIT)
{
// alarm1();
}
}
It gave printed this as I by mistake had used the wrong ports. Problem solved. Be sure to check your connections after an extra time!
Related
I need to write a program in Arduino that turns ON or OFF two LEDs independently depending on the data received via serial communication. For example, the first LED will turn on if the Arduino board receives a1,and it will turn OFF if a2 is received. but I require help on doing this. i havent started on this yet but i am trying to do it using 2 blinking light code. I am new to Arduino programming and i don't understand some concepts. but i can definitely use help on doing this.
int LEDred = 3;
int LEDgreen = 6;
void setup() {
pinMode (LEDred, OUTPUT);
pinMode (LEDgreen, OUTPUT);
}
void loop() {
digitalWrite (LEDred, HIGH);
digitalWrite (LEDgreen, LOW);
delay (1000);
digitalWrite (LEDred, LOW);
digitalWrite (LEDgreen, HIGH);
delay (1000);
}
Use 1 or 2 instead of a1 and a2. Because it's easier to process.Consider you send 1 via serial port. Read the signal by
byte val;
if(Serial.available()>0){
val=Serial.read();
}
Then use another if statement in order to blink red or green LED
I have a strange problem, I have Arduino UNO/MEGA and I need to get Gyro sensors's data and I want to see the data in the serial monitor. Seems like a simple task, I wrote a simple C program which collects data from Arduino through serial monitor I can see the data. Everything is working for few minutes and after that, it stops.
This code is supposed to calculate a distance travelled in a line using encoder (PID algorithm implemented using Gyroscope data for straight motion) after reaching desired position, machine takes a U-Turn.
It stop for a second after taking the U-Turn and then starts straight motion again. The problem I'm facing is that the gyroscope readings stop randomly while machine taking the turn. Due to this, the machine keeps rotating about that point without stopping.
#include <Wire.h>
#include <MPU6050.h>
MPU6050 mpu;
float timeStep = 0.01, yaw=0;
const int motor11=6;//LEFT MOTOR FW
const int motor12=7;//LEFT MOTOR BK
const int motor1pwm=3;
const int motor21=8;//RIGHT MOTOR FW
const int motor22=9;//RIGHT MOTOR BK
const int motor2pwm=5;
int flag1 = 0;
int thres1=120;//PWM Values
int thres2=120;
void setup()
{
Serial.begin(115200);
// Initialize MPU6050
while(!mpu.begin(MPU6050_SCALE_2000DPS, MPU6050_RANGE_2G))
{
Serial.println("Could not find a valid MPU6050 sensor, check wiring!");
delay(500);
}
mpu.calibrateGyro();
mpu.setThreshold(1);
pinMode(motor11, OUTPUT);
pinMode(motor12, OUTPUT);
pinMode(motor1pwm, OUTPUT);
pinMode(motor21, OUTPUT);
pinMode(motor22, OUTPUT);
pinMode(motor2pwm, OUTPUT);
}
void loop()
{
Vector norm=mpu.readNormalizeGyro();
yaw=yaw+norm.ZAxis*timeStep;
if(flag1 == 0){
straight();
}
if(flag1 == 2){
taketurn();
}
}
void straight()
{
digitalWrite(motor11, HIGH);
digitalWrite(motor12, LOW);
analogWrite(motor1pwm, thres1);
digitalWrite(motor21, HIGH);
digitalWrite(motor22, LOW);
analogWrite(motor2pwm, thres2);
delay(8000);
flag1 = 2;
}
void taketurn()
{
float setPoint = yaw - 500;
digitalWrite(motor11, HIGH);
digitalWrite(motor12, LOW);
analogWrite(motor1pwm, 120);
digitalWrite(motor21, LOW);
digitalWrite(motor22, LOW);
analogWrite(motor2pwm, 120);
while(true)
{
Vector norm = mpu.readNormalizeGyro();
yaw = yaw + norm.ZAxis * timeStep;
Serial.print("Turning Yaw= ");
Serial.println(yaw);
if(setPoint >= yaw) {
digitalWrite(motor11, LOW);
digitalWrite(motor12, LOW);
analogWrite(motor1pwm, thres2);
digitalWrite(motor21, LOW);
digitalWrite(motor22, LOW);
analogWrite(motor2pwm, thres1);
delay(2000);
break;
}
}
flag1 = 0;
}
The serial monitor just stops displaying the reading. This does not happen every time, and it is very random. I want to get proper and continuous data. Is it a logical problem or a board problem?
Normally a random crash would indicate possibly unhandled interrupts or memory overwrite, but looking at your code and it being an Arduino program, it's unlikely to be either. I don't see any divide ops either, so you are not dividing by zero. The two possible things I see is that a) you have a "while (true)" without exit, so surely that could get you into trouble, and b) perhaps your delay functions are called with a very large value unexpectedly, and the MCU is actually just delaying a long time.
I was getting to know this ultrasonic detector with a simple code. All I was looking for was an output (my LED) to light up whenever the detector sensed an object within so many centimetres.
However the LED remains lit and the serial monitor just keeps spitting out the value '0.00cm'
I would appreciate any help, thanks.
(I do apologise if there is a very simple error I have overlooked)
#include <NewPing.h>
int TriggerPIN = 2;
int EchoPIN = 3;
int LEDPIN = 7;
void setup()
{
Serial.begin(9600);
//That started the distance monitor
pinMode(LEDPIN, OUTPUT);
pinMode(TriggerPIN, OUTPUT);
pinMode(EchoPIN, INPUT);
}
void loop()
{
float Distance, Duration;
digitalWrite(TriggerPIN, LOW);//These three blink the distance LED
delayMicroseconds(2);
digitalWrite(TriggerPIN, HIGH);
delayMicroseconds(10);
digitalWrite(TriggerPIN, LOW);
Duration = pulseIn(EchoPIN, HIGH); //Listening and waiting for wave
Distance = (Duration*0.034/2);//Converting the reported number to CM
if (Distance > 50)
{
digitalWrite(LEDPIN,LOW);
}
else
{
digitalWrite(LEDPIN,HIGH);
}
Serial.print(Distance);Serial.print("cm");
Serial.println(" ");
delay(200);
}
A couple of things to try:
Change the serial print to display 'Duration', to see if the problem lies in the centimetre conversion.
If this is not the problem:
(Assuming you are using the NewPing 1.7 library, as found here. )
The NewPing library has a built in 'Ping' function, along with distance conversion.
Try replacing the start of your code with this:
#include <NewPing.h>
#define TRIGGER_PIN 2
#define ECHO_PIN 3
#define MAX_DISTANCE 200 // Maximum distance to ping for (cm). Up to ~450cm
NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE); // NewPing setup of pins and maximum distance.
You do not need to then set the Trigger and Echo pins as outputs in your setup.
In your main loop, use these methods to get time and distance in microsecs and centimetres:
unsigned int pingTime = sonar.ping(); //Gets the ping time in microseconds.
Serial.print(sonar.convert_cm(pingTime)); // Convert ping time in cm, serial out.
I hope this helps.
I am doing a basic project in Arduino UNO connecting an Ultra Sonic sensor (HC-SR04) which should print in the serial monitor the distance of the closest object but it always print 0.
This is my code:
long distance;
long time;
void setup(){
Serial.begin(9600);
pinMode(4, OUTPUT);
pinMode(2, INPUT);
}
void loop(){
digitalWrite(2,LOW);
delayMicroseconds(5);
digitalWrite(2, HIGH);
delayMicroseconds(10);
time = pulseIn(4, HIGH);
distance = int(0.017*time);
Serial.print("Distance: ");
Serial.print(distance);
Serial.println(" cm.");
delay(1000);
}
And this is the breadboard:
The primary issue that I see is that your code doesn't match your wiring diagram.
For example, your diagram shows Trig connected to pin 4. The Trig should be the output from your Arduino but you have it defined as an input.
The Echo is connected to pin 2 and it should be an input, but you have it defined as an output.
Finally, in your loop(), you are not even using pin 2 or pin 4, but pins 9 and 8. Another issue is the timing you use in setting the trigger pulse - it does not match the datasheet. I would do something like this (assuming that you are actually connected to the pins shown in your diagram):
#define sensorTrigPin 4
#define sensorEchoPin 2
void setup()
{
Serial.begin(9600);
pinMode(sensorTrigPin, OUTPUT);
pinMode(sensorEchoPin, INPUT);
}
void loop()
{
int pulseWidth = 0;
digitalWrite(sensorTrigPin, HIGH);
delayMicroseconds(10);
digitalWrite(sensorTrigPin, LOW);
pulseWidth = pulseIn(sensorEchoPin, HIGH);
Serial.print("Pulse Width: ");
Serial.print(pulseWidth);
delay(1000);
}
Note that pulseWidth is just the amount of time that it takes from the beginning of the Echo pulse going high to the end of the same pulse (when it goes low). You would still have to calculate the distance based on the value of pulseWidth.
UPDATE BASED ON RECENT EDIT TO THE QUESTION
If you change a portion of your loop() code to this, it should work:
void loop(){
digitalWrite(4, HIGH); //was (2, LOW)
delayMicroseconds(10); //was (5)
digitalWrite(4, LOW); //was (2, HIGH)
//REMOVED EXTRA DELAY
time = pulseIn(2, HIGH); //was (4,HIGH);
... //Keep the rest of your code the same.
}
Try connecting your VCC of the sensor to 3V3 instead of 5V. This might sound odd, but I tried it and it worked well. Also, please make sure that your echo and trig pin match the code.
I would like to restart the arduino board but keeping values of some variable. My solution would be calling setup() whenever I would like to restart. Something like this:
int led = 13;
int led2 = 50;
boolean restart = false;
void setup() {
pinMode(led, OUTPUT);
pinMode(led2, OUTPUT);
if(!restart){
digitalWrite(led, LOW); // will only happen once
delay(3000);
}
digitalWrite(led, HIGH); // turn the LED on (and will be always on even after reset)
restart = true;
delay(3000);
digitalWrite(led2, HIGH); // indicate restart is called
delay(1000);
digitalWrite(led2, LOW);
setup();}
void loop() { }
I was thinking if this will cause any heavy usage in RAM. Or is there any better methods?
Thank you.
Use the EEPROM library. Have a button with an interrupt that saves the variable then read the variable in the setup() routine.
If you are getting or changing information slow enough you could constantly write the value but beware EEPROM on this chip is only certified to 100,000 writes per byte.