I've written the following code to light up a row of LEDs one at a time.
int ledPins[] = {7,8,9,10,11,12,13};
void setup() {
for (int i = 0; i < sizeof(ledPins); i++) {
pinMode(ledPins[i], OUTPUT);
}
}
void loop() {
for (int i = 0; i < sizeof(ledPins); i++) {
digitalWrite(i, HIGH);
delay(1000);
digitalWrite(i, LOW);
delay(1000);
}
}
The above works fine. However after completing the for loop there is a long delay (about 10 seconds) before it repeats.
Why would there be such a long delay? Is this expected or is it a problem with my code?
the function sizeof(array) return the size of the array in the memory, in bytes. and because sizeof(int) is probably not 1, you get a larger value than expected.
sizeof can be use to determine the number of elements in an array, by taking the size of the entire array and dividing it by the size of a single element.
so this line:
for (int i = 0; i < sizeof(ledPins); i++) {
should be rewritten as:
for (int i = 0; i < sizeof(ledPins) / sizeof(int); i++) {
see:
http://en.wikipedia.org/wiki/Sizeof
In this case as the array has a fixed size it's simpler to do this:
#define NO_LEDS 7
int ledPins[NO_LEDS] = {7,8,9,10,11,12,13};
void setup() {
for (int i = 0; i < NO_LEDS; i++) {
pinMode(ledPins[i], OUTPUT);
}
}
Or move the calculation of the array's size into a variable and use that.
int ledPins[] = {7,8,9,10,11,12,13};
int noLeds;
void setup() {
noLeds = sizeof(ledPins) / sizeof(int);
for (int i = 0; i < noLeds; i++) {
pinMode(ledPins[i], OUTPUT);
}
}
Related
I wrote a program for Arduino UNO with attached Funshield, which will animate the following pattern on the four vertical LEDs.At any given moment, exactly one LED (of four) is turned on (we are starting with the topmost one). In each step of the animation, the active LED moves one slot down. When it hits the bottom, it bounces and moves upwards again, until it reaches top. The animation repeats itself forever.
One step of the animation takes exactly 300ms
#include <funshield.h>
int ledPin[] = {led1_pin, led2_pin, led3_pin, led4_pin};
void setup() {
for (int i = 0; i<5; i++)
pinMode(ledPin[i], OUTPUT);
}
void loop() {
int i = 0;
for (i = 5-1; i>=0; i--)
digitalWrite(ledPin[i], LOW);
delay(1000);
digitalWrite(ledPin[i], HIGH);
for (i; i<5; i++) {
digitalWrite(ledPin[i], LOW);
delay(500);
digitalWrite(ledPin[i], HIGH);
}
}
if i using the delay() function, it works perfectly，but when i used millis() function , 4 LEDs light up at the same time.I would like to know what is causing the animation to stall.
#include "funshield.h"
unsigned long startMillis;
unsigned long currentMillis;
const unsigned long period = 300;
const byte liu = 4;
int ledPin[] = { led1_pin, led2_pin, led3_pin, led4_pin };
void setup() {
for (int i = 0; i < 5; i++)
pinMode(ledPin[i], OUTPUT);
startMillis = millis();
}
void loop()
{
currentMillis = millis();
if (currentMillis - startMillis >= period)
int i = 0;
for (int i = 0; i > 4; i++) {
digitalWrite(liu, !digitalRead(liu));
digitalWrite(ledPin[i], LOW);
digitalWrite(ledPin[i], HIGH);
startMillis = currentMillis;
}
for (int i = 4; i >= 0; i--) {
digitalWrite(liu, !digitalRead(liu));
digitalWrite(ledPin[i], LOW);
digitalWrite(ledPin[i], HIGH);
startMillis = currentMillis;
}
}
first of all unsigned long nowTime; should be at the top, outside of your loop
secondly, you need to use nowTime = millis(); for the specific time that you want to record the current time (this should be before you use the (millis()-nowtime>300)
and lastly, remove (unsigned long)
from this line
if(unsigned long)(millis()-nowtime>300)
for further clarification on how to use millis, read this article on arduino's official website
I'm working on a circuit that has two separate 4-bit binary counters with LEDs. I press a button and one counter begins counting to 15 in binary. I press a second button and the first counter pauses where it is and the second group of LEDs begin counting to 15 in binary. I got both counters working, but I can't get the first group to pause and the second to begin. I've tried using if statements with a boolean flag, but it messes up the first group of LEDs. How can I get ledPins1[] to pause when button2 is pressed, then resume when ledPins2[] finish?
int ledPin1[] = {2,3,4,5};
int ledPin2[] = {7,8,9,10};
int button1 = 11;
int button2 = 12;
boolean button1Last = LOW;
boolean button1Current = LOW;
boolean button2Last = LOW;
boolean button2Current = LOW;
void setup()
{
pinMode(button1, INPUT);
pinMode(button2, INPUT);
for(int i=0; i<4; i++)
{
pinMode(ledPin1[i], OUTPUT);
}
for(int i=0; i<4; i++)
{
pinMode(ledPin2[i], OUTPUT);
}
}
boolean waitForButtonPush1 (boolean lastStartSwitchState1)
{
boolean currentStartSwitchState1 = digitalRead(button1);
if(lastStartSwitchState1 != currentStartSwitchState1) delay(20);
currentStartSwitchState1 = digitalRead(button1);
return currentStartSwitchState1;
}
boolean waitForButtonPush2 (boolean lastStartSwitchState2)
{
boolean currentStartSwitchState2 = digitalRead(button2);
if(lastStartSwitchState2 != currentStartSwitchState2) delay(20);
currentStartSwitchState2 = digitalRead(button2);
return currentStartSwitchState2;
}
void loop()
{
button1Current = waitForButtonPush1(button1Last);
if(button1Last == LOW && button1Current == HIGH)
{
for (byte counter =0;counter<=15; counter++)
{
displayBinary(counter);
delay(500);
}
}
button2Current = waitForButtonPush2(button2Last);
if(button2Last == LOW && button2Current == HIGH)
{
for (byte counter =0;counter<=15; counter++)
{
displayBinary2(counter);
delay(500);
}
}
}
void displayBinary(byte numToShow)
{
for (int i =0;i<4;i++)
{
if (bitRead(numToShow, i)==1)
{
digitalWrite(ledPin1[i], HIGH);
}
else
{
digitalWrite(ledPin1[i], LOW);
}
}
}
void displayBinary2(byte numToShow)
{
for (int i =0;i<4;i++)
{
if (bitRead(numToShow, i)==1)
{
digitalWrite(ledPin2[i], HIGH);
}
else
{
digitalWrite(ledPin2[i], LOW);
}
}
}
Welcome to the world of embedded devices!
Getting a small microprocessor to do several things at the same time is a bit tricky.
The key is to never block. No calls to delay(), no sending large buffers on the serial port at 9600 bauds in one go, etc...
There are some simple techniques to do it, one of the most commonly used is finite state machines.
Let's analyse your app a bit.
2 similar dssplay counters, with delay
2 buttons, buttons usually need to be debounced, that also involves a delay.
Some code, for you to tinker with:
// ****************************
// pinout
static const byte ledPin1[] = { 2, 3, 4, 5 };
static const byte ledPin2[] = { 7, 8, 9, 10 };
constexpr byte button1 = 11; // using constexpr for these saves 2 bytes of RAM.
constexpr byte button2 = 12;
// ****************************
// Counter data
static constexpr unsigned int led_delay = 500; // 500 ms, for all counters.
// constexpr ?? arduino supports c++17. Not all features in the main .ino
// module and all features in .cpp modules.
// Hint: you could have a member variable in the structure below for delay,
// this would allow for counters running at different speeds, or add buttons
// to increase/decrease speed.
// we have only 2 states, but you could add more, like running
// backwards, or run a different chase pattern maybe?
enum class led_counter_state : byte
{
stopped,
running,
};
struct led_counter_data_t
{
led_counter_state state; // STATE
byte counter; // counter current value
unsigned int timestamp; // used for timing.
const byte* leds; // LED pins.
};
static led_counter_data_t led_counter[2];
void led_display_init()
{
for (byte i = 0; i < 2; ++i)
{
led_counter[i].state = led_counter_state::stopped;
led_counter[i].counter = 0;
led_counter[i].timestamp = 0;
}
led_counter[0].leds = ledPin1;
led_counter[1].leds = ledPin2;
}
// ****************************
// LED cotrrol
static void leds_display_value(const led_counter_data_t& cntr)
{
for (byte i = 0, val = cntr.counter; i < 4; ++i, val >>= 1)
digitalWrite(cntr.leds[i], val & 0x01);
}
static void leds_control(led_counter_data_t& cntr)
{
const auto now = (unsigned int)millis(); // keep track of time.
switch(cntr.state)
{
default: // something is wrong.. stop.
cntr.state = led_counter_state::stopped;
// fall through ...
case led_counter_state::stopped:
return; // if not running, do nothing
case led_counter_state::running:
if (now - cntr.timestamp >= led_delay) // check delay
{
if (++cntr.counter > 15) // advance counter.
cntr.counter = 0;
leds_display_value(cntr); // show value.
cntr.timestamp = now; // keep track of time.
}
break;
}
}
static void leds_start(led_counter_data_t& cntr)
{
if (cntr.state != led_counter_state::stopped)
return;
cntr.state = led_counter_state::running;
if (++cntr.counter > 15) // advance counter.
cntr.counter = 0;
led_display_value(cntr); // show value.
cntr.timestamp = (unsigned int)millis();
}
static void leds_stop(led_counter_data_t& cntr)
{
cntr.state = led_counter_state::stopped;
}
// ****************************
// switch inputs data
static constexpr byte switch_debounce_delay = 30; // 30ms is a good value for
// debouncing
struct switch_data_t
{
byte sw1_state : 1; // no need to waste more than 1 bit per switch
byte sw2_state : 1;
byte timestamp; // we'll only count to 30 ms, so 1 byte timestamp will do
};
static switch_data_t switch_data;
// ****************************
// switch inputs code
static void control_inputs()
{
const auto now = (byte)millis();
if (now - switch_data.timestamp < switch_debounce_delay)
return;
switch_data.timestamp = now;
// All switch control logic is regrouped here, and isolated
// form other control code, this makes the logic easier to
// write, read, and debug.
bool b = digitalRead(button1);
if (b & !switch_data.sw1_state) // button was pushed right now.
{
if (led_counter[0].state == led_counter_state::stopped)
{
leds_start(led_counter[0]); // start counter 1
leds_stop(led_counter[1]); // stop counter 2
}
else
{
leds_stop(led_counter[0]); // stop counter 1
}
}
switch_data.sw1_state = b;
b = digitalRead(button2);
if (b & !switch_data.sw2_state) // button was pushed right now.
{
if (led_counter[1].state == led_counter_state::stopped)
{
leds_start(led_counter[1]); // start counter 2
leds_stop(led_counter[0]); // stop counter 1
}
else
{
leds_stop(led_counter[1]); // stop counter 2
}
}
switch_data.sw2_state = b;
}
// ****************************
void setup()
{
pinMode(button1, INPUT);
pinMode(button2, INPUT);
for (byte i = 0; i < 4; ++i)
{
digitalWrite(ledPin1[i], LOW);
pinMode(ledPin1[i], OUTPUT);
digitalWrite(ledPin2[i], LOW);
pinMode(ledPin2[i], OUTPUT);
}
led_display_init();
}
// ****************************
// The goal, always, is to exit loop() as fast as possible, so
// everything will run smoothly, and appear to run simultaneously.
void loop()
{
control_inputs();
leds_control(led_counter[0]);
leds_control(led_counter[1]);
}
I do not have an arduino with me, so I did not comppile nor ran this, but it should be pretty close. Let me know if you're having issues or have any questions.
im having a problem, i just bought an arduino and i was wondering if anyone could help, here is my code. (i am just trying to get two leds to fade in and out).
int ledCount = 2;
int ledPins [ ] = {11,12 };
int brightness = 0;
int delayTime = 10;
void setup() {
pinMode(ledPins, OUTPUT);
}
void loop() {
while(brightness < 255)
{
analogWrite(ledPins, brightness);
delay(delayTime);
brightness = brightness + 1;
}
while(brightness > 0)
{
analogWrite(ledPins, brightness);
delay(delayTime);
brightness = brightness - 1;
}
}
You are passing an array to analogWrite or pinMode, where it is expecting a uint8_t.
Arduino pin manipulation functions will only handle a single pin at a time. There are ways around that, by directly manipulating the AVR/ARM GPIO registers, but those can be finicky (not recommended for use unless you really need speed).
The reason it says int * is because under the hood, arrays in C/C++ are represented as pointers.
If you want to analogWrite or pinMode to both LEDs, you will have to call the function once for each LED. Example:
analogWrite(ledPins[0], brightness);
analogWrite(ledPins[1], brightness);
Or
for(int currentLED = 0;currentLED < ledCount;i++){
analogWrite(ledPins[currentLED], brightness);
}
In the context of your program:
int ledCount = 2;
int ledPins [] = {11, 12};
int brightness = 0;
int delayTime = 10;
#define INCREASE 1
#define DECREASE 2
int brightness_change = INCREASE;
void setup(){
for(int i = 0;i < ledCount;i++){
pinMode(i, OUTPUT);
}
}
void loop(){
while(brightness < 255 && brightness_change == INCREASE){
brightness = brightness + 1;
}
while(brightness > 0 && brightness_change == DECREASE){
brightness = brightness - 1;
}
if(brightness == 255){
brightness_change = DECREASE;
}
if(brightness == 0){
brightness_change = INCREASE;
}
for(int current_led = 0;current_led < ledCount;current_led++){
analogWrite(current_led, brightness;
}
delay(delayTime;
}
Not tested, but it should work.
This game has 4 leds and 4 buttons. the game is turning RANDOMLY those leds ON and OFF.
The player should be able to push the right button whenever he sees one led to be turned ON.
The leds should be turning ON and OFF with incerasing speed, so reaction time of a player is shorter and shorter
I have this code but i just know how to add more leds and buttons.
const int BUTTON1 = A0;
const int BUTTON2 = A1;
const int BUTTON3 = A2;
const int BUTTON4 = A3;
int LED1 = 2;
int LED2 = 3;
int LED3 = 4;
int LED4 = 5;
int ran;
int right = 0;
int ledOrder[9];
int guessOrder[9];
void setup()
{
Serial.begin(9600);
pinMode(LED1,OUTPUT);
pinMode(LED2,OUTPUT);
pinMode(LED3,OUTPUT);
pinMode(LED4,OUTPUT);
pinMode(BUTTON1,INPUT);
pinMode(BUTTON2,INPUT);
pinMode(BUTTON3,INPUT);
pinMode(BUTTON4,INPUT);
}
void randomLed() {
for (int i = 0; i < 9; i++) {
ran = random(1,20);
if (ran < 11) {
digitalWrite(LED1,HIGH);
delay(500);
digitalWrite(LED1,LOW);
ledOrder[i] = 1;
}
else {
digitalWrite(LED2,HIGH);
delay(500);
digitalWrite(LED2,LOW);
ledOrder[i] = 2;
}
delay(500);
}
}
void btnClick() {
int ans = 0;
while (ans < 9) {
if (digitalRead(BUTTON1) == HIGH) {
guessOrder[ans] = 1;
ans++;
while (digitalRead(BUTTON1) == HIGH) {
}
}
else if (digitalRead(BUTTON2) == HIGH) {
guessOrder[ans] = 2;
ans++;
while (digitalRead(BUTTON2) == HIGH) {
}
}
}
}
void loop() {
Serial.print("Press button1 to start \n");
while (digitalRead(BUTTON1) == LOW) {
}
randomLed();
btnClick();
for (int i = 0; i < 9; i = i + 1) {
Serial.print("Guess: ");
Serial.print(guessOrder[i]);
Serial.print(" Answer: ");
Serial.print(ledOrder[i]);
if (guessOrder[i] == ledOrder[i]) {
Serial.print(" Right");
right++;
} else {
Serial.print(" Wrong");
}
Serial.print("\n ");
}
Serial.print(right);
Serial.print("/9\n");
delay(2000);
}
If I understand your question correctly, you would like to increase the led blink rate(when the LED's come on) each time the user gets the previous game right. If this is true you should try to put loop in for/if the user got the the previous one(game) right it will increase blink rate by a simple increment( I++;). Comment if you feel this is clarified enough or if your asking for something else
I'm a newbie when it comes to electronics and Arduino - so the best way is to just to play around with it, right?
I have started a small project that utilize and LDR (Light Density Resistor) and want to use it to calculate the frequency that a light beam is blocked or turned off.
For debugging purposes I setup a small LED that blinks at a defined frequency (5 Hz etc.) and use a LCD to display the output.
I have a problem with my top right corner... It seems as it performs wrongly. It was the intention that it should show the registered frequency, but while debugging I have set it to show the number of counts in an interval of 5 sec (5,000 msec). But it appears as 24 is the max no matter what frequency I set (When I get it to show the right number [5 sec x 5 Hz = 25] I will divide by the time interval and get the results in Hz). It also shows 24.0 for 9 Hz etc..
I also have this: YouTube video
...but some fumbling in the beginning caused the LED to move a bit so it counted wrong. But in the end it "works".. But the 24.0 keeps being constant
This is my code:
#include <LiquidCrystal.h>
LiquidCrystal lcd(7, 8, 9, 10, 11 , 12);
int booBlocked = 0;
int counter = 0;
int checkValue = counter + 1;
int ledPin = 3; // LED connected to digital pin 3
int value = LOW; // previous value of the LED
long previousMillis = 0; // will store last time LED was updated
long freqency = 5; // Hz (1/sec)
long thousand = 1000;
long interval = thousand / freqency; // milliseconds
//long interval = 59; // interval at which to blink (milliseconds)
int tValue = 0; // Threshold value used for counting (are calibrated in the beginning)
long pMillis = 0;
long inter = 5000;
int pCount = 0;
float freq = 0; // Calculated blink frequency...
void setup() {
lcd.begin(16, 2);
lcd.setCursor(0,1); lcd.print(interval);
lcd.setCursor(4,1); lcd.print("ms");
pinMode(ledPin, OUTPUT); // sets the digital pin as output
lcd.setCursor(0,0); lcd.print(freqency);
lcd.setCursor(4,0); lcd.print("Hz");
}
void loop() {
// Print LDR sensor value to the display
int sensorValue = analogRead(A0);
lcd.setCursor(7,1);
lcd.print(sensorValue);
delay(100);
if (millis() > 5000){
doCount(sensorValue);
updateFreq();
lcd.setCursor(7+5,0);
lcd.print(freq);
} else {
setThresholdValue(sensorValue);
lcd.setCursor(7+5,1);
lcd.print(tValue);
}
// LED BLINK
if (millis() - previousMillis > interval) {
previousMillis = millis(); // remember the last time we blinked the LED
// if the LED is off turn it on and vice-versa.
if (value == LOW)
value = HIGH;
else
value = LOW;
digitalWrite(ledPin, value);
}
}
void updateFreq(){
long now = millis();
long t = now - pMillis;
if (t >= 10000) {
freq = (float) (counter - pCount);
//freq = ((float) (counter - pCount)) / (float) 10.0;
pMillis = now; // remember the last time we blinked the LED
pCount = counter;
}
}
void setThresholdValue(int sensorValue){
if (sensorValue > int(tValue/0.90)){
tValue = int (sensorValue*0.90);
}
}
void doCount(int sensorValue){
// Count stuff
if (sensorValue < tValue){
booBlocked = 1;
//lcd.setCursor(0,0);
//lcd.print("Blocked");
} else {
booBlocked = 0;
//lcd.setCursor(0,0);
//lcd.print(" ");
}
if (booBlocked == 1) {
if (counter != checkValue){
counter = counter + 1;
lcd.setCursor(7,0);
lcd.print(counter);
}
} else {
if (counter == checkValue){
checkValue = checkValue + 1;
}
}
}
UPDATE
A more "clean" code (please see my own answer)
#include <LiquidCrystal.h>
// Initiate the LCD display
LiquidCrystal lcd(7, 8, 9, 10, 11 , 12); // see setup at http://lassenorfeldt.weebly.com/1/post/2013/02/ardunio-lcd.html
long updateInterval = 150; // ms
long updateTime = 0;
// Declare the pins
int ledPin = 3; // LED connected to digital pin 3
// LED setup
int value = LOW; // previous value of the LED
long previousMillis = 0; // will store last time LED was updated
long freqency = 16; // Hz (1/sec)
long thousand = 1000;
long blinkInterval = thousand / freqency; // milliseconds
//// LDR counter variables ////
// Counting vars
static int counter = 0;
int booBlocked = 0;
int checkValue = counter + 1;
// Calibration vars
long onBootCalibrationTime = 5000; // time [time] to use for calibration when the system is booted
static int threshold = 0; // Value used for counting (calibrated in the beginning)
float cutValue = 0.90; // Procent value used to allow jitting in the max signal without counting.
// Frequency vars
float freq = 0; // Calculated blink frequency...
long frequencyInterval = 5000; // time [ms]
long pMillis = 0;
int pCount = 0;
void setup() {
// Setup the pins
pinMode(ledPin, OUTPUT); // sets the digital pin as output
// display static values
lcd.begin(16, 2);
lcd.setCursor(0,0); lcd.print(freqency);
lcd.setCursor(4,0); lcd.print("Hz");
lcd.setCursor(0,1); lcd.print(blinkInterval);
lcd.setCursor(4,1); lcd.print("ms");
// Setup that allows loggin
Serial.begin(9600); // Allows to get a readout from Putty (windows 7)
}
void loop() {
long time = millis();
int sensorValue = analogRead(A0);
// Blink the LED
blinkLED(time);
// Calibrate or Count (AND calculate the frequency) via the LDR
if (time < onBootCalibrationTime){
setThresholdValue(sensorValue);
} else {
doCount(sensorValue);
updateFreq(time);
}
// Update the LCD
if (time > updateTime){
updateTime += updateInterval; // set the next time to update the LCD
// Display the sensor value
lcd.setCursor(7,1); lcd.print(sensorValue);
// Display the threshold value used to determined if blocked or not
lcd.setCursor(7+5,1); lcd.print(threshold);
// Display the count
lcd.setCursor(7,0);
lcd.print(counter);
// Display the calculated frequency
lcd.setCursor(7+5,0); lcd.print(freq);
}
}
void blinkLED(long t){
if (t - previousMillis > blinkInterval) {
previousMillis = t; // remember the last time we blinked the LED
// if the LED is off turn it on and vice-versa.
if (value == LOW)
value = HIGH;
else
value = LOW;
digitalWrite(ledPin, value);
}
}
void setThresholdValue(int sValue){
if (sValue > int(threshold/cutValue)){
threshold = int (sValue*cutValue);
}
}
void doCount(int sValue){
if (sValue < threshold){
booBlocked = 1;
} else {
booBlocked = 0;
}
if (booBlocked == 1) {
if (counter != checkValue){
counter = counter + 1;
}
} else {
if (counter == checkValue){
checkValue = checkValue + 1;
}
}
}
void updateFreq(long t){
long inter = t - pMillis;
if (inter >= frequencyInterval) {
freq = (counter - pCount) / (float) (inter/1000);
pMillis = t; // remember the last time we blinked the LED
pCount = counter;
}
}
This code does not fix my question, but is just more easy to read.
The issue with your plan is that a light density resistor is going to pick up all the ambient light around and therefore be completely environment sensitive.
Have any other project hopes? This one seems like an engineering learning experience, not a coding one.
Have you thought of motor projects? Personally I'm more into home automation, but motor projects are almost instantly rewarding.
I'd recommend to re-write your doCount() function along these lines to make things simpler and easier to grasp:
void doCount(int sensorValue){
static int previousState;
int currentState;
if ( previousState == 0 ) {
currentState = sensorValue > upperThreshold;
} else {
currentState = sensorValue > lowerThreshold;
}
if ( previousState != 0 ) {
if ( currentState == 0 ) {
counter++;
}
}
previousState = currentState;
}
Let lowerThreshold and upperThreshold be, for example, 90% and 110%, respectively, of your former tValue, and you have a hysteresis to smoothen the reaction to noisy ADC read-outs.
I think i found one of the bugs.. I was using a delay() which caused some trouble..
I cleaned up the code:
#include <LiquidCrystal.h>
// Initiate the LCD display
LiquidCrystal lcd(7, 8, 9, 10, 11 , 12); // see setup at http://lassenorfeldt.weebly.com/1/post/2013/02/ardunio-lcd.html
long updateInterval = 150; // ms
long updateTime = 0;
// Declare the pins
int ledPin = 3; // LED connected to digital pin 3
// LED setup
int value = LOW; // previous value of the LED
long previousMillis = 0; // will store last time LED was updated
long freqency = 16; // Hz (1/sec)
long thousand = 1000;
long blinkInterval = thousand / freqency; // milliseconds
//// LDR counter variables ////
// Counting vars
static int counter = 0;
int booBlocked = 0;
int checkValue = counter + 1;
// Calibration vars
long onBootCalibrationTime = 5000; // time [time] to use for calibration when the system is booted
static int threshold = 0; // Value used for counting (calibrated in the beginning)
float cutValue = 0.90; // Procent value used to allow jitting in the max signal without counting.
// Frequency vars
float freq = 0; // Calculated blink frequency...
long frequencyInterval = 5000; // time [ms]
long pMillis = 0;
int pCount = 0;
void setup() {
// Setup the pins
pinMode(ledPin, OUTPUT); // sets the digital pin as output
// display static values
lcd.begin(16, 2);
lcd.setCursor(0,0); lcd.print(freqency);
lcd.setCursor(4,0); lcd.print("Hz");
lcd.setCursor(0,1); lcd.print(blinkInterval);
lcd.setCursor(4,1); lcd.print("ms");
// Setup that allows loggin
Serial.begin(9600); // Allows to get a readout from Putty (windows 7)
}
void loop() {
long time = millis();
int sensorValue = analogRead(A0);
// Blink the LED
blinkLED(time);
// Calibrate or Count (AND calculate the frequency) via the LDR
if (time < onBootCalibrationTime){
setThresholdValue(sensorValue);
} else {
doCount(sensorValue);
updateFreq(time);
}
// Update the LCD
if (time > updateTime){
updateTime += updateInterval; // set the next time to update the LCD
// Display the sensor value
lcd.setCursor(7,1); lcd.print(sensorValue);
// Display the threshold value used to determined if blocked or not
lcd.setCursor(7+5,1); lcd.print(threshold);
// Display the count
lcd.setCursor(7,0);
lcd.print(counter);
// Display the calculated frequency
lcd.setCursor(7+5,0); lcd.print(freq);
}
}
void blinkLED(long t){
if (t - previousMillis > blinkInterval) {
previousMillis = t; // remember the last time we blinked the LED
// if the LED is off turn it on and vice-versa.
if (value == LOW)
value = HIGH;
else
value = LOW;
digitalWrite(ledPin, value);
}
}
void setThresholdValue(int sValue){
if (sValue > int(threshold/cutValue)){
threshold = int (sValue*cutValue);
}
}
void doCount(int sValue){
if (sValue < threshold){
booBlocked = 1;
} else {
booBlocked = 0;
}
if (booBlocked == 1) {
if (counter != checkValue){
counter = counter + 1;
}
} else {
if (counter == checkValue){
checkValue = checkValue + 1;
}
}
}
void updateFreq(long t){
long inter = t - pMillis;
if (inter >= frequencyInterval) {
freq = (counter - pCount) / (float) (inter/1000);
pMillis = t; // remember the last time we blinked the LED
pCount = counter;
}
}
Its not as precise as I wished.. but I believe that this is might due to the way I blink the LED.
I also discovered that float cutValue = 0.90; has an influence... lowering the bar to 0.85 decrease the calculated frequency.. ??
I changed the code completely after Albert was so kind to help me out using his awesome FreqPeriodCounter library
I also added a potentiometer to control the frequency
Here is my code:
#include <FreqPeriodCounter.h>
#include <LiquidCrystal.h>
// FrequencyCounter vars
const byte counterPin = 3; // Pin connected to the LDR
const byte counterInterrupt = 1; // = pin 3
FreqPeriodCounter counter(counterPin, micros, 0);
// LCD vars
LiquidCrystal lcd(7, 8, 9, 10, 11 , 12); // see setup at http://lassenorfeldt.weebly.com/1/post/2013/02/ardunio-lcd.html
long updateInterval = 200; // ms
long updateTime = 0;
// LED vars
int ledPin = 5; // LED connected to digital pin 3
int value = LOW; // previous value of the LED
float previousMillis = 0; // will store last time LED was updated
static float freqency; // Hz (1/sec)
static float pfreqency;
static float blinkInterval; // milliseconds
boolean logging = true; // Logging by sending to serial
// Use potentiometer to control LED frequency
int potPin = 5; // select the input pin for the potentiometer
int val = 0; // variable to store the value coming from the sensor
void setup(void){
// Setup the pins
pinMode(ledPin, OUTPUT); // sets the digital pin as output
val = analogRead(potPin);
freqency = map(val, 0, 1023, 0, 25); // Hz (1/sec)
pfreqency = freqency;
blinkInterval = 1000 / (freqency*2); // milliseconds
// LCD display static values
lcd.begin(16, 2);
lcd.setCursor(0,0); lcd.print(freqency);
lcd.setCursor(4,0); lcd.print("Hz");
lcd.setCursor(14,0); lcd.print("Hz");
lcd.setCursor(0,1); lcd.print(blinkInterval);
lcd.setCursor(4,1); lcd.print("ms");
//
attachInterrupt(counterInterrupt, counterISR, CHANGE);
// Logging
if (logging) {Serial.begin(9600);}
}
void loop(void){
// Loop vars
float time = (float) millis();
float freq = (float) counter.hertz(10)/10.0;
// Blink the LED
blinkLED(time);
if (logging) {
if(counter.ready()) Serial.println(counter.hertz(100));
}
// Update the LCD
if (time > updateTime){
updateTime += updateInterval; // set the next time to update the LCD
lcdNicePrint(7+3, 0, freq); lcd.setCursor(14,0); lcd.print("Hz");
val = analogRead(potPin);
freqency = map(val, 0, 1023, 1, 30);
if (freqency != pfreqency){
pfreqency = freqency;
blinkInterval = 1000 / (freqency*2); // milliseconds
lcdNicePrint(0,0, freqency); lcd.setCursor(4,0); lcd.print("Hz");
lcd.setCursor(0,1); lcd.print(blinkInterval);
lcd.setCursor(4,1); lcd.print("ms");
}
}
}
void lcdNicePrint(int column, int row, float value){
lcd.setCursor(column, row); lcd.print("00");
if (value < 10) {lcd.setCursor(column+1, row); lcd.print(value);}
else {lcd.setCursor(column, row); lcd.print(value);}
}
void blinkLED(long t){
if (t - previousMillis > blinkInterval) {
previousMillis = t; // remember the last time we blinked the LED
// if the LED is off turn it on and vice-versa.
if (value == LOW)
value = HIGH;
else
value = LOW;
digitalWrite(ledPin, value);
}
}
void counterISR()
{ counter.poll();
}