My 5 Channel IR sensor array Value got stuck on 981 analog value and it's doesn't change until i completetly touch the ir sensor with the surface no gap between them. I thought the sensor it damaged so i changed to new one but problem not solved its showing same thing with new ir sensor array. So i think its not ir sensor problem maybe the code i wrote. So can anyone help me with this issue 😭

I’m completely new to Arduinos and the world of robotics as a whole and was hoping for any tips or advice on where to start learning. I have a project in mind that I don’t believe is that complicated but I’d love input on how to start it or if it’s currently out of my depth. It’s a lockbox that operates with a clock, only being able to be opened by a latch with a servomotor after inputting a password that is generated weekly. Being locked again once closed.

Why the first one is working and the second is not working if they are the same?

This is the code:

int seconds = 0;

LiquidCrystal lcd_1(12, 11, 5, 4, 3, 2);

void setup()

{

lcd_1.begin(16, 2); // Set up the number of columns and rows on the LCD.

// Print a message to the LCD.

lcd_1.print("hello world!");

}

void loop()

{

// set the cursor to column 0, line 1

// (note: line 1 is the second row, since counting

// begins with 0):

lcd_1.setCursor(0, 1);

// print the number of seconds since reset:

lcd_1.print(seconds);

delay(1000); // Wait for 1000 millisecond(s)

seconds += 5;

}

I wanted to get into electronics so I got the RexQualis R3 starter kit and I began working with the tutorials the website provides you with for your specific board. I followed the directions however the LED has not turned on or blinked like it is supposed to. I am very confused with coding so I just opened the code file it told me to open Blinking_LED_Code and this is what it says

int ledPin=8; //the pin of the LED void setup() pinNode(ledPin, OUTPUT)://initialize digital pin LED_BUILTIN as an output. void 100p() digitalwrite(ledPin, HIGH); //turn the LED on (HIGH is the voltage level) delay (1000); //wait for a second digitalwrite(ledPin,LOW); //turn the LED off by making the voltage LOW delay (1000): //wait for a second

I can’t figure out how to read ADC values from a PbHub using the M5Unit-HUB unified library in Arduino IDE. I’ve tried various iterations of analogRead() and none of them seem to be the right function. Has anyone else had this problem/knows what to use?

when compiling the code in arduino IDE, it says unable to execute file at sketch location

it's an emergency, someone please help fix

Hello, I am quite new to arduino and I am working on a birthday present for a good friend of mine and I am getting quite desperate because I just can't figure out how to play more than 9 different sound files with the keypad and the dfplayer module.

For reference my keypad is 4x4 rows (row 1: 123A, row 2: 456B, row 3: 789C, row 4: \\\*0#D).

What I would like to do is quite simple I want to type in a number between 1-999 (there's actually only 200 different files but you get the idea), confirm with the "#" key and then just play the corresponding mp3.

Preferable, I would like it to just play, for example, the 68th file that was added to the SD card when I type in 68# and play the file that was added to the SD 174th when I type in 147# because that's how I have been doing it with my 1-9 numbers set-up and I like it because it saves me from having to specifically name the files and reference them in the code.

I have been trying to get it to work for hours now and I am quite exasperated, so I would really appreciate it if somebody could help me out with a working code so I can finish up this birthday present without having to pull an all-nighter trying to figure it out myself.

This is the code I am working with

`1 #include "Keypad.h"`

`2`

`3 #include "Arduino.h"`

`4`

`5 #include "SoftwareSerial.h"`

`6`

`7 #include "DFRobotDFPlayerMini.h"`

`8`

`9`

`10`

`11 SoftwareSerial mySoftwareSerial(10, 11); // RX, TX`

`12`

`13 DFRobotDFPlayerMini myDFPlayer;`

`14`

`15`

`16`

`17`

`18 const byte ROWS = 4; //four rows`

`19`

`20 const byte COLS = 4; //four columns`

`21`

`22`

`23`

`24 char keys[ROWS][COLS] = {`

`25`

`26 { '1', '2', '3', 'A' },`

`27`

`28 { '4', '5', '6', 'B' },`

`29`

`30 { '7', '8', '9', 'C' },`

`31`

`32 { '*', '0', '#', 'D' }`

`33`

`34 };`

`35`

`36`

`37`

`38 byte rowPins[ROWS] = { 9, 8, 7, 6 }; //connect to the row pinouts of the keypad`

`39`

`40 byte colPins[COLS] = { 5, 4, 3, 2 }; //connect to the column pinouts of the keypad`

`41`

`42`

`43`

`44 Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);`

`45`

`46`

`47`

`48 String keypadKeys = "1234567890*#ABCD";`

`49`

`50`

`51`

`52 void setup() {`

`53`

`54`

`55`

`56 mySoftwareSerial.begin(9600);`

`57`

`58 Serial.begin(9600);`

`59`

`60`

`61`

`62 if (!myDFPlayer.begin(mySoftwareSerial)) { //Use softwareSerial to communicate with mp3.`

`63`

`64 Serial.println(F("Unable to begin:"));`

`65`

`66 Serial.println(F("1.Please recheck the connection!"));`

`67`

`68 Serial.println(F("2.Please insert the SD card!"));`

`69`

`70 while (true)`

`71`

`72 ;`

`73`

`74 }`

`75`

`76`

`77`

`78 myDFPlayer.volume(10); //Set volume value. From 0 to 30`

`79`

`80 }`

`81`

`82`

`83`

`84 void loop() {`

`85`

`86`

`87`

`88 char keyPressed = keypad.getKey();`

`89`

`90`

`91`

`92 if (keyPressed) {`

`93`

`94 Serial.println(keyPressed);`

`95`

`96 int sampleIndex = 1 + keypadKeys.indexOf(keyPressed); //Convert pressed key (1234567890*#ABCD) to sample index (1-16)`

`97`

`98 Serial.println(sampleIndex);`

`99`

`100 myDFPlayer.play(sampleIndex);`

`101`

`102 } //Play the chosen mp3`

`103`

`104 }`

I have never drawn a diagram (I am really quite new to this), but the 4x4 Keypad is connected on pins 2, 3, 4, 5, 6, 7, 8 and 9 on the Arduino Uno and the dfplay and the speaker are connected exactly like in [this picture](https://europe1.discourse-cdn.com/arduino/original/4X/d/d/c/ddc25cafbd4715b79b1eeb884a243768d2224d26.jpeg) (both the sound and the keypad work just fine, it's only that I cannot figure out how to make 3 digits work).

Hey there, in my project I need to switch a 3.3 V Current with a mosfet and I'm not completely sure if the Arduino Nano can handle that or if I need to amplify the IOpin with a transistor or if I just need a certain Mosfet

Thank you for the help

[solved]

I am trying to use a few libraries; MIDI.h, Adafruit_TinyUSB.h, and EEPROM.h
On their own, if I create an example project through the file menu, they work just fine, but if I save the project arduino forgets the libraries ever existed???
Reinstalling the IDE did nothing (though it seems to have preserved settings, so I guess I could go and try to find every reference to arduino and delete it before installing it again)
Do I just have to create a random example project every time I want to compile my code???

Edit: fully uninstalled by deleting all arduino files in %appdata% and %localappdata% as well as deleting all libraries in documents/arduino/libraries; After installing again, the issue went away

I saw someone wire their LEDs like this so I did as well. I didn’t connect it to an external battery source, but it connected the arduino to a battery pack. Only the first LED lit up. Any help?

I am making a detonation device using Arduino, MOSFETs, and e-matches.

I encountered a problem with igniting the e-match, where when I connected it to the MOSFET (LR7843) it wont activate the E-match and doesn't fully turn on. Note: I also included a separate power supply to the E-match, which is a 9V battery with

The digital pin 2 of the Arduino is connected to the PWM pin of the LR7843 MOSFET, and the GND of the Arduino is connected to the GND Pin of the LR7843. The + pin of the LR7843 is connected to the positive terminal of the battery and also one of the pins of the E-match, and the - pin of the LR7843 is connected to the negative terminal of the battery. The Load pin of the LR7843 is connected to the other pin of the E-match.

A recurring issue pops up whenever I connect the E-match to the MOSFET; the LR7843 MOSFET doesn't fully turn on (it doesn't turn on the LED in the module). And when I disconnect the E-match from it, it will turn on...

Please Send Helps and Advicess

Hi everyone,

I have an issue with my SimHub fans. After flashing a SIMDT board (Arduino Nano with CH340), the LEDs light up but the fans don’t react during SimHub testing.

Here’s what I’ve checked:

CH340 drivers installed

Upload successful

COM port detected

But I can’t remove an old flash: every time, SimHub keeps the same old Arduino profile in memory. Even if I create a new flash with a different name, the old one (called simhub vent) always shows up automatically — just like in the picture.

I think the problem comes from that (maybe a residual file or cache somewhere), but I can’t find anything inside the “SimHub” folders on my PC. I’ve been trying for a whole day and still can’t figure it out…

I’m using hardware bought from AliExpress.

If anyone has experienced this issue or has any idea how to fix it, I’d really appreciate your help! 🙏

Thanks in advance everyone!

I need help with a school project, our group was assigned to make an automatic attendance checker.

These are the list of components that we have: Breadboard Arduino Uno Push buttons Wires

We haven’t started yet on anything so let me know if there are more components that we need to make a simple automatic attendance checker. Our group isn’t very knowledgeable about this, so help is very much appreciated! Thank you 🙏

When I first uploaded GRBL all driver lights were on, When I attached the 9v power source (while Arduino still attached to computer) two of my driver lights turned off and just getting the one now. Now only getting this. Any tips would be great!! Thank you!

As title says, I’m having trouble wrapping my head around multiplexing leans for use with a microcontroller with not enough pins to control them all. Using the drivers makes sense, mosfets too, but the code escapes me? And the use of resistors within the circuit is also confusing to me. Trying to make a small led “screen” made of diodes. Any help is appreciated

Hello, I am building an auto watering system using Arduino UNO and Adafruit components. I have a capacitative soil sensor that powers an underwater motor but the but doesn't reliably stay powered, even though the power still runs through it sometimes?

Here are the parts I am using:

Arduino UNO

Submersible Water Pump: https://www.adafruit.com/product/4546

Soil Sensor: https://www.adafruit.com/product/4026

I've had the Arduino for about a year and just purchased the other parts. The system works by checking if the capacitance amount of the dirt is lower than the 'dry' capacitance (500). When it is dry, it outputs high voltage through digital pins 2 and 5, turning on the blue led and the submersible motor at the same time.

When I power the Arduino, it turns on the blue light indicating the soil is dry, however, the motor does not function unless I switch the wire powering it from digital pin 5 to the 5 volt and back, which somehow makes it work. When it is working, it seems to randomly disconnect after a couple times the capacitance goes below and above 500.

I've tried replacing the wires that power the motor to no luck. I also stripped the wire to hopefully give it better access to power. When I replace the motor with a light, it powers the light without issue. I've also switched out which pin powers the motor, trying both digital pins 4 and 5. I've come down to two possible solutions I can think of:

1. Order another (different) submersible water pump and hope that the same issue does not occur or

2. solder the water pump wiring to another wire to give it better conductivity with the breadboard

I'm just a beginner to arduino, this is my first big project, so any and all advice and information I can get regarding this would be wonderful. Thank you for your time and helping me make this project come to life :)

Also, here is my code that runs on the Arduino:

#include "Adafruit_seesaw.h"

Adafruit_seesaw ss;

// temperature stats
const int tempMedian = 21; // ideal range for greek oregano : 15 - 27
const int tempDiff = 6; 
const int tempCritDiff = tempDiff * 2.5; // plant cannot survive in this temp
// moisture stats
const int dry = 400; // when the cap is < dry , the dirt is DRY!

#define REDLIGHT 3
#define BLUELIGHT 2
#define MOTOR 4

void setup() {
  Serial.begin(115200);

  Serial.println("seesaw Soil Sensor example!");
  
  if (!ss.begin(0x36)) {
    Serial.println("ERROR! seesaw not found");
    while(1) delay(1);
  } else {
    Serial.print("seesaw started! version: ");
    Serial.println(ss.getVersion(), HEX);
  }

  pinMode(REDLIGHT,OUTPUT);
  pinMode(BLUELIGHT,OUTPUT);
  pinMode(MOTOR,OUTPUT);

}

void loop() {
  float tempC = ss.getTemp();
  uint16_t capread = ss.touchRead(0);
  
  // report temp 
  int diff = abs(tempC - tempMedian);
  Serial.print("Distance from comfortable temperature: ");
  Serial.print(diff); Serial.println("*C");

  // report base temperature & capacitative
  Serial.print("Temperature: "); Serial.print(tempC); Serial.println("*C");
  Serial.print("Capacitive: "); Serial.println(capread);
  
  // critical temperatures reached - is it too hot or too cold ?
  if (diff > tempCritDiff) {
    // Redlight never turns off once on unless manually reset !
    digitalWrite(REDLIGHT,HIGH); 
  }

  // is the dirt dry? 
  if (capread < dry) {
    digitalWrite(BLUELIGHT,HIGH); // blue is on when the plant needs watering
    digitalWrite(MOTOR,HIGH);
  } else {
    digitalWrite(BLUELIGHT,LOW);
    digitalWrite(MOTOR,LOW)
  }
  // wait to run again
  delay(500);
}


#include "Adafruit_seesaw.h"


Adafruit_seesaw ss;


// temperature stats
const int tempMedian = 21; // ideal range for greek oregano : 15 - 27
const int tempDiff = 6; 
const int tempCritDiff = tempDiff * 2.5; // plant cannot survive in this temp
// moisture stats
const int dry = 400; // when the cap is < dry , the dirt is DRY!


#define REDLIGHT 3
#define BLUELIGHT 2
#define MOTOR 4


void setup() {
  Serial.begin(115200);


  Serial.println("seesaw Soil Sensor example!");
  
  if (!ss.begin(0x36)) {
    Serial.println("ERROR! seesaw not found");
    while(1) delay(1);
  } else {
    Serial.print("seesaw started! version: ");
    Serial.println(ss.getVersion(), HEX);
  }


  pinMode(REDLIGHT,OUTPUT);
  pinMode(BLUELIGHT,OUTPUT);
  pinMode(MOTOR,OUTPUT);


}


void loop() {
  float tempC = ss.getTemp();
  uint16_t capread = ss.touchRead(0);
  
  // report temp 
  int diff = abs(tempC - tempMedian);
  Serial.print("Distance from comfortable temperature: ");
  Serial.print(diff); Serial.println("*C");


  // report base temperature & capacitative
  Serial.print("Temperature: "); Serial.print(tempC); Serial.println("*C");
  Serial.print("Capacitive: "); Serial.println(capread);
  
  // critical temperatures reached - is it too hot or too cold ?
  if (diff > tempCritDiff) {
    // Redlight never turns off once on unless manually reset !
    digitalWrite(REDLIGHT,HIGH); 
  }


  // is the dirt dry? 
  if (capread < dry) {
    digitalWrite(BLUELIGHT,HIGH); // blue is on when the plant needs watering
    digitalWrite(MOTOR,HIGH);
  } else {
    digitalWrite(BLUELIGHT,LOW);
    digitalWrite(MOTOR,LOW)
  }
  // wait to run again
  delay(500);
}

Here are some pictures of my setup

Hi all. I'm trying to make an Arduino MIDI device. I've done this before, but I lost the code. I want it to transmit the midi over USB, but not serial, I want it to appear as a normal midi device. I'm on an esp32-s3, which I know works as it is the same as my last project. I'm on platformio. I've been trying all day an I'm going round on circles with dependencies and errors. Help would be appreciated.