Hi, I have just started using Arduino and want to make a project. This project involves 4 LED's which light up sequentially and using a potentiometer to define the speed with which the LED's turn on and off one by one. Now I want the pushbutton for beginning and stopping of the loop at the LED whose turn it is. But my pushbutton is acting as a push and release instead of a toggle. What changes should I apply to the code so that the pushbutton acts as toggle instead of push and release.
The code is;
#define LED_1_PIN 13
#define LED_2_PIN 12
#define LED_3_PIN 11
#define LED_4_PIN 10
#define BUTTON 2
#define LED_NUMBER 4
#define potPin A0
int val = 0;
int buttonState = 0;
int buttonPressCount = 0;
void setup()
{
pinMode(LED_1_PIN, OUTPUT);
pinMode(LED_2_PIN, OUTPUT);
pinMode(LED_3_PIN, OUTPUT);
pinMode(LED_4_PIN, OUTPUT);
Serial.begin(9600);
}
void loop()
{
int val = analogRead(0);
val = map(val, 0, 1023, 0, 255);
analogWrite(9, val);
buttonState = digitalRead(BUTTON);
if (buttonState == LOW) {
if (buttonPressCount % LED_NUMBER == 0) {
digitalWrite(LED_1_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_1_PIN, LOW);delay(val);
}
if (buttonPressCount % LED_NUMBER == 1) {
digitalWrite(LED_2_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_2_PIN, LOW);delay(val);
}
if (buttonPressCount % LED_NUMBER == 2) {
digitalWrite(LED_3_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_3_PIN, LOW);delay(val);
}
if (buttonPressCount % LED_NUMBER == 3) {
digitalWrite(LED_4_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_4_PIN, LOW);delay(val);
}
buttonPressCount++;
Serial.println(val);
}
}
You need to detect when the button becomes pressed rather than when it is pressed
See the StateChangeDetection example in the IDE
I tried to implement the recommended example in my code, but now the button does not function at all. I can't understand what I did wrong, please help. Attaching the new code:
#define LED_1_PIN 13
#define LED_2_PIN 12
#define LED_3_PIN 11
#define LED_4_PIN 10
#define BUTTON 2
#define LED_NUMBER 4
#define potPin A0
int val = 0;
int buttonState = 0;
int buttonPressCount = 0;
int buttonPushCounter = 0;
int lastButtonState = 0;
void setup()
{
pinMode(LED_1_PIN, OUTPUT);
pinMode(LED_2_PIN, OUTPUT);
pinMode(LED_3_PIN, OUTPUT);
pinMode(LED_4_PIN, OUTPUT);
Serial.begin(9600);
}
void loop()
{
if (buttonState != lastButtonState) {
if (buttonState == HIGH) {
buttonPushCounter++;
Serial.println("on");
Serial.print("number of button pushes: ");
Serial.println(buttonPushCounter);
} else {
Serial.println("off");
}
delay(50);
}
lastButtonState = buttonState;
int val = analogRead(0);
val = map(val, 0, 1023, 0, 255);
analogWrite(9, val);
buttonState = digitalRead(BUTTON);
if (buttonPushCounter % LED_NUMBER == 0) {
digitalWrite(LED_1_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_1_PIN, LOW);delay(val);
}
if (buttonPushCounter % LED_NUMBER == 1) {
digitalWrite(LED_2_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_2_PIN, LOW);delay(val);
}
if (buttonPushCounter % LED_NUMBER == 2) {
digitalWrite(LED_3_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_3_PIN, LOW);delay(val);
}
if (buttonPushCounter % LED_NUMBER == 3) {
digitalWrite(LED_4_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_4_PIN, LOW);delay(val);
}
buttonPushCounter++;
Serial.println(val);
}
buttonPushCounter++;
You are doing this unconditionally in loop() rather than when a change of button state is detected
So should I remove it or change the place it is written? because if I remove it the LED's are not lighting up sequentially but instead lighting after I press the button. I want them to light sequentially and when I press the button the LED to stop and when I press it again, it continues to light sequentially from where it was paused
Put it in the right place, ie when a change of state is detected. The example code shows you how
After doing it the LED's are not lighting up sequentially, but each of them is lighting after I press the button. Whereas I want that when I press the button the LED to stop and when I press it again, it continues to light sequentially from where it was paused
The code:
#define LED_1_PIN 13
#define LED_2_PIN 12
#define LED_3_PIN 11
#define LED_4_PIN 10
#define BUTTON 2
#define LED_NUMBER 4
#define potPin A0
int val = 0;
int buttonState = 0;
int buttonPressCount = 0;
int buttonPushCounter = 0;
int lastButtonState = 0;
void setup()
{
pinMode(LED_1_PIN, OUTPUT);
pinMode(LED_2_PIN, OUTPUT);
pinMode(LED_3_PIN, OUTPUT);
pinMode(LED_4_PIN, OUTPUT);
Serial.begin(9600);
}
void loop()
{
if (buttonState != lastButtonState) {
if (buttonState == HIGH) {
buttonPushCounter++;
Serial.println("on");
Serial.print("number of button pushes: ");
Serial.println(buttonPushCounter);
} else {
Serial.println("off");
}
delay(50);
}
lastButtonState = buttonState;
int val = analogRead(0);
val = map(val, 0, 1023, 0, 255);
analogWrite(9, val);
buttonState = digitalRead(BUTTON);
if (buttonPushCounter % LED_NUMBER == 0) {
digitalWrite(LED_1_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_1_PIN, LOW);delay(val);
}
if (buttonPushCounter % LED_NUMBER == 1) {
digitalWrite(LED_2_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_2_PIN, LOW);delay(val);
}
if (buttonPushCounter % LED_NUMBER == 2) {
digitalWrite(LED_3_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_3_PIN, LOW);delay(val);
}
if (buttonPushCounter % LED_NUMBER == 3) {
digitalWrite(LED_4_PIN, HIGH);delay(val);
}
else
{
digitalWrite(LED_4_PIN, LOW);delay(val);
}
Serial.println(val);
}
As a starting point I would suggest putting the LED pin numbers in an array and using the value of buttonPushCounter as the index to the array. This will avoid the need for multiple if/else
I was able to put LED PIN numbers in an array, but can't understand how to get the function I wanted for my pushbutton.
The code is:
#define LED_NUMBER 4
#define potPin A0
#define BUTTON 2
int val = 0;
int buttonPushCounter = 0;
int buttonState = 0;
int lastButtonState = 0;
void setup()
{
for (int thisPin = 9; thisPin < 13; thisPin++)
pinMode(thisPin, OUTPUT);
pinMode(BUTTON, INPUT);
Serial.begin(9600);
}
void loop()
{
int val = analogRead(0);
val = map(val, 0, 1023, 0, 255);
for (int thisPin = 9; thisPin < 13; thisPin++) {
digitalWrite(thisPin, HIGH);
delay(val);
digitalWrite(thisPin, LOW);
}
}
There is no array in the code in your reply
Sorry for that, I got a bit confused.
#define LED_NUMBER 4
#define potPin A0
#define BUTTON 2
int ledPins[] = {
9, 12, 11, 10
};
int val = 0;
int buttonPushCounter = 0;
int buttonState = 0;
int lastButtonState = 0;
void setup()
{
for (int thisPin = 9; thisPin < 13; thisPin++)
pinMode(thisPin, OUTPUT);
pinMode(BUTTON, INPUT);
Serial.begin(9600);
}
void loop()
{
int val = analogRead(0);
val = map(val, 0, 1023, 0, 255);
for (int thisPin = 9; thisPin < 13; thisPin++) {
digitalWrite(thisPin, HIGH);
delay(val);
digitalWrite(thisPin, LOW);
}
}
OK, the LED pins are in an array but you don't use it
Re-reading your original post I see that the value of buttonPressCount simply starts/stops the LED sequence rather than being an index to the LED array
Start simple with something like this
for (int p = 0; p < 4; p++)
{
pinMode(ledPins[p], OUTPUT); //the pin numbers do not need to be contiguous
}
Later in the code, you can use the value of ButtonPressCount to control whether the for loop runs
if (buttonPressCount % 2) //odd or even ?
{
int val = analogRead(0);
val = map(val, 0, 1023, 0, 255);
for (int p = 0; p < 4; p++)
{
digitalWrite(ledPins[p], HIGH);
delay(val);
digitalWrite(ledPins[p], LOW);
}
}
NOTE : this is not the best way to do this but try it first
I did try it but now the LED's won't turn on itself. I also didn't understand what you meant by odd or even? @UKHeliBob
The code:
int pinCount = 4;
#define potPin A0
#define BUTTON 2
int ledPins[] = {
9, 12, 11, 10
};
int val = 0;
int buttonPressCount = 0;
int buttonState = 0;
void setup()
{
for (int p = 9; p < 13; p++)
{
pinMode(ledPins[p], OUTPUT);
}
Serial.begin(9600);
}
void loop()
{
buttonState = digitalRead(BUTTON);
if (buttonPressCount % 2)
{
int val = analogRead(0);
val = map(val, 0, 1023, 0, 255);
for (int p = 0; p < 4; p++)
{
digitalWrite(ledPins[p], HIGH);
delay(val);
digitalWrite(ledPins[p], LOW);
}
}
}
for (int p = 9; p < 13; p++)
{
pinMode(ledPins[p], OUTPUT);
}
Start by using the correct values in the pinMode() for loop. Look at my code in reply #12
After doing it but removing{ if (buttonPressCount % 2) //odd or even ? }, the code works without doing the pushbutton functionality. Kindly advise what to do after.
The code is:
#define LED_NUMBER 4
#define potPin A0
#define BUTTON 2
int ledPins[] = {
9, 12, 11, 10
};
int val = 0;
int buttonPressCount = 0;
int buttonState = 0;
int lastButtonState = 0;
void setup()
{
for (int p = 0; p < 4; p++)
{
pinMode(ledPins[p], OUTPUT);
}
pinMode(BUTTON, INPUT);
Serial.begin(9600);
}
void loop() {
int val = analogRead(0);
val = map(val, 0, 1023, 0, 255);
for (int p = 0; p < 4; p++)
{
digitalWrite(ledPins[p], HIGH);
delay(val);
digitalWrite(ledPins[p], LOW);
}
}
Let's deal with the code as it is first. For instance, how long will the LED pin stay LOW ?
EDIT - ignore that question
How is the button wired ? Does the pin go HIGH or LOW when you press the button ? Do you have a pullup or pulldown resistor in place to keep it in a known state at all times ?
Hi,
Can you please post a circuit diagram of your project, a hand drawn image will be fine.
As I look through each edit of your code this line appears in one and not the other;
pinMode(BUTTON, INPUT);
You must have this in all your codes for your button to be read.
As @UKHeliBob has asked, how have you wired your button?
Tom... 
Hello
Check this IDE Example to continue.
Have a nice day and enjoy coding in C++.
Hi, this is the project I am working on. In this version the potentiometer is working and the lights are lighting up sequentially. But the pushbutton is not working. I want the pushbutton to stop the sequence, when the pushbutton is pressed once and stop at whatever light the sequence is on, and when I press the pushbutton again I want the sequence to continue. Kindly help since I am not understanding how to add the IDE example to it.
Hi,
PLEASE draw your circuit, pen(cil) and paper.
You have a mass of green wires that form a tangled mess.
Have you got some simple code that JUST tests your buttons?
Do you have a DMM?
You need to connect your tactile button like this;
Use the diagonally opposite connections, to ensure you have the switch in circuit.
Tom...
