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The Arduino Uno is the most common of the Arduino boards. It is based on the ATmega328P microcontroller.

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connecting multiple sensors [on hold]

i want to connect a humidity,moisture and temperature sensor to a micro controller which controller shall i use and how?
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17 views

UNO + ESP8266-01 Send UDP/OSC -> OSX (MAX/MSP) [on hold]

I am unable to set it up. I want UNO to read some sensor data -> ESP8266 should transmit this sensor data to OSX. I want ESP to act like Access Point. And read incoming changes from uno and transmit ...
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0answers
6 views

Two HC05 Bluetooth Bind problem

I succeeded in giving an AT command. My two BL MAC addresses are 21, 13, A03B and 21, 13, A3E2. When I want to connect one to the other I use AT+BIND=21,13,A3E2. But then I see Error(7). If I use ...
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0answers
17 views

How to attach a counter sensor which should work in between two flags?

I want to attach a counter sensor which should work in between two flags. My code for measuring speed between two flags fixed at 30 m spacing is below: const int laserPin = 2; int laser =0; volatile ...
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0answers
24 views

My Arduino is not working with the LCD [on hold]

I have this code, and I have wired everything properly but the LCD is not displaying anything. Can someone help? #include<LiquidCrystal.h> LiquidCrystal lcd(13,12,11,10,9,8); #include <...
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3answers
35 views

Need help with a program for a button to change the display on an OLED display

So I am programming an OLED display from my Arduino Uno. I am trying to have a button that switches the different words on the display. (The words are just placeholders for programs as of now.) My ...
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4answers
73 views

Can you help me trim my code?

First of all I want to be clear, I'm not very skilled in programming methods, all the C I learned was for various Arduino projects. That being said, I just finished a project that reads some data ...
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0answers
12 views

How to connect hc-05 module and pH sensor at a time with Arduino Uno? [on hold]

I am new to Arduino world!, now how to connect hc-05 module and pH sensor at a time with Arduino Uno?
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1answer
7 views

How to share/Reassign analog pin for two Adafruit libraries for two adafruit hardware

I'm attempting to use the Adafruit BMP180 and Adafruit 16x2 RGB LCD Display together on the same Arduino Uno R1. Both the pieces of hardware and their libraries use Analog Pin 4 and 5. Is there any ...
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1answer
64 views

Why does the potentiometer act as an on/off switch in my program?

I'm using an HC-SRO4 Ultrasonic Sensor and a D10K Potentiometer. So, I was just messing around with the potentiometer in the program and then tried to change the brightness of the LED which turns on ...
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1answer
12 views

Can I use GSM and Data Logger Shield at the same time on one Arduino?

Me and my classmates are trying to make an arduino base project where we will be using sensors, GSM, and Data logger shield. We want the arduino to store the data collected and at the same time send a ...
1
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1answer
73 views

Uno pin connection: Atmega16u2 & ATmega328P

On my Uno, I set up the HoodLoader2 (link below) so I can program both the ATMega16u2 and the ATmega328P. I can communicate between the two using the serial port. However, I need the serial port to ...
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0answers
5 views

Ads1292r - printing filtered ecg data [on hold]

I am using one of the libraries from Protocentral and their ads1292r shield. I am trying to print filtered ecg data to serial monitor, but I am not sure I am getting the right values. This is the ...
1
vote
1answer
18 views

Problems improving the inquiry speed of Bluetooth HC-05

I'm buiding a project with the Arduino and Bluetooth HC-05 module that receives the MACs of Bluetooth devices around (does not connect, just inquiry). It works, but I want a better performance in ...
1
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1answer
19 views

avrdude ser_open() can't set com-state

When trying to upload the blink sketch to my (unofficial) Arduino Uno, I get the following error: avrdude ser_open() can't set com-state for "\\.\COM3" I have programmed this Arduino before using ...
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1answer
29 views

Pointer memory allocation in function

I would like to know how Arduino allocate memory for pointers in function arguments. For instance. I have this code that use 192 bytes (Arduino IDE compiler: Global variables use 192 bytes (9%) of ...
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1answer
35 views

Arduino fingerprint verification from server

I am thinking to do a hobby project related to fingerprint verification. The flow which I wanted to implement is something like below: A user can register a fingerprint using an Arduino device This ...
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1answer
32 views

Is SRAM erased when putting Arduino into sleep_mode_pwr_down?

Question In the interest of reducing power consumption, I am putting the Arduino into sleep mode between taking sensor readings. However, the data from readings are stored in arrays, and must not be ...
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0answers
15 views

How can I create a chatbot using Uno R3 and HC08? [on hold]

I want to be able to connect through a mobile app and chat with a siri like assistant. Can anyone help me have a working sketch?
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0answers
18 views

Timer issue in Arduino mega [on hold]

Right now I'm working on stepper motors and using PWM.h library I'm giving different frequencies to both stepper motor. Earlier I'm using Arduino UNO but now I'm using Arduino Mega. When I'm working ...
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2answers
37 views

Nema 17, Arduino Uno and stepper motor drive ~2H42B

I tried running Nema 17 stepper motor using the drive in the pic below (not the basic L298N drive, which BTW I successfully used to rotate the motor) . Could any of you review my existing connections ...
1
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1answer
39 views

Device Security - EEPROM data [duplicate]

I'm writing code for Arduino that I plan to distribute. But I worry about piracy (the .HEX can extracted from the board and reuploaded to another). With that in mind, I am storing data to the EEPROM. ...
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0answers
16 views

Arduino Uno - How to write personal data in NTAG213 using RFID-RC522

I am trying to write some data in NTAG213 sticker with this code: #include <SPI.h> #include <MFRC522.h> constexpr uint8_t RST_PIN = 9; // Configurable, see typical pin layout above ...
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1answer
39 views

Difference in pinout (types?) Uno/Mega

As a hands-on guy, I've started my first ever Arduino project 5 hours ago with no prior knowledge about Arduinos (I have coding experience tho. included this in case I am missing something obvious to ...
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4answers
1k views

Some Arduino components seem ridiculously cheap

My project is an Arduino-based device, packed into a box. It will need to use Speed, Latitude, Longitude and Altitude data to log hills it detects on to an SD. On the press of a button, it will need ...
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votes
1answer
63 views

Button state issue

Let me preface this by saying I'm a beginner, and I know my code must have some logic errors. I need some fresh eyes on this, I have been messing with it a few days and am just running in circles at ...
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0answers
6 views

Error uploading sketch to Arduino Uno

I get this error while uploading sketch, any help ? Arduino: 1.8.0 (Windows 10), Board: "Arduino/Genuino Uno" E:\INSTALLATION\ARDUINO IDE\Arduino\arduino-builder -dump-prefs -logger=machine -...
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0answers
16 views

External EEPROM write/read problems (Arduino Uno)

I have Arduino Uno(Atmega328p) and external EEPROM connected via I2C. My code in Arduino Studio: #include <Wire.h> #include <Adafruit_GFX.h> #include <Adafruit_SSD1306.h> #define ...
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1answer
64 views

Interrupts Problem with Flow sensor

#include <Wire.h> //I2C lib #include <LCD.h> #include <LiquidCrystal_I2C.h> // LCD lib LiquidCrystal_I2C lcd(0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE); const int pot_pin = A0; const ...
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0answers
10 views

Send quaternion values over BLE instead of fusionData.x()

I'm using a 9 axis sensor to determine the angle of rotation (ST LSM9DS1 9-Axis DOF) In the main script the following function is called to get one of the angles, in this example it is the angle with ...
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1answer
32 views

I want to make my stepper motor work for 1 hour [closed]

I already tried code that makes the stepper motor work for a few minutes only. I'm using a clock module, a DS1302 and the stepper library already present. Also the driver I'm using is an L298n. If ...
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0answers
24 views

Question regarding the Arduino PID Library

I've been looking to implement a PID controller on my Arduino. I've taken a control systems class, so my first instinct was to generate a step response and approximate the system in MATLAB/Simulink ...
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2answers
56 views

Bad request on esp-01 connection [closed]

i'm working with a partner on a iot solution with esp-01. We are trying to send data from a current sensor and using a esp-01 via http requests to a server, then we store it in a MySql database. The ...
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1answer
12 views

How do I pull chip select pin up and down, when I have CAN shield and Newhaven Display 4.3CTP-SHIELD-N share the same chip select pin(10)?

I am currently working on an Arduino project, which must be able to listen to the data going through CAN bus and display it on the Touchscreen LCD Newhaven Display 4.3CTP-SHIELD-N. Problem is that ...
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1answer
19 views

checking the line for the content of the word [closed]

I have such string: engine:255b How i can check is there a word (engine) in the line? And how i can got int 255? Please, help me)
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votes
1answer
24 views

Controlling servo via serial port without any delay [duplicate]

I have such code: void setup() { Serial.begin(9600); } void loop() { } void serialEvent() { while (Serial.available()) { Serial.println(Serial.readString()); } } When I send there ...
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0answers
20 views

Why pulse sensor give high bpm?

I make project to detect bpm with pulse sensor, I try use sample code from Pulse Sensor Playground Getting Bpm to Monitor. this is the code : #define USE_ARDUINO_INTERRUPTS true #include <...
1
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1answer
88 views

Wake up a PC from an Uno

I want to wake up a PC via a USB-connected Arduino. When using a Pro Micro (Leonardo) I can do it, as its HID interface can wake up a PC. That is, in the Device Manager, under "Keyboards", the ...
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3answers
64 views

Using EEPROM Anything in loop()

I'm trying to make a programm for Arduino Bluno Beetle, that saves a string in the loop. Here is my code: #include <EEPROM.h> #include <EEPROMAnything.h> struct config_t{ String ...
1
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1answer
36 views

Arduino sensing its 'Motion'

I am working on a project where I need the Arduino to 'sense' at what direction its moving. For example, I want the Arduino to 'sense' that it is moving towards 'forward' direction, 'backwards' ...
0
votes
1answer
33 views

The voltage level fluctuates whenever ESP8266 receives signal [closed]

Good afternoon dear community, I am trying to built a WiFi communication with Arduino using ESP8266 module. There is one servo, one step motor connected to Arduino and whenever the ESP8266 Wi-Fi ...
0
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3answers
68 views

Can multiple Arduinos be connected to a single relay?

I have a 16 channel relay that will basically manage 16 different contacts. However, each channel in the relay needs to be controlled by an individual Arduino. So in total I would have 16 different ...
1
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3answers
112 views

How to print 'µ' in the serial monitor?

I have been trying to print the letter µ on the Serial Monitor of Arduino IDE but I failed to do so. Is there any way to print µ or any other Non ASCII characters such as Ó,ß,Ô,Ò,õ,Õ,þ, etc using ...
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1answer
42 views

How to automatically reset the nrf24l01+ with code?

I have two separate nrf24l01+ connected to two different Arduino UNOs, one as TX and the other as RX. The problem is the connection stops after a while between them. On the Arduino COM screen I have ...
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1answer
21 views

Ethernet socket impedes adding shields

I just bought a KEYESTUDIO W5500 Ethernet Arduino without realizing that the Ethernet socket on the board impedes adding any additional shields to the device because: Horizontally the socket runs ...
0
votes
1answer
28 views

Button Matrix Code and Wiring [closed]

Bear with me here, I'm new to arduinos, so what I'm saying might only make sense in my own mind. I'm trying a button matrix and I not completely sure on my wiring and I have a few questions. Is the ...
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votes
0answers
31 views

Reading and writing on same serial

I am trying to connect over same serial 2 servos and distance sensor. In Arduino, I have this code. If I write in Arduino's serial monitor values for my servos like 120,120, it works. I wrote a ...
0
votes
1answer
27 views

How to change the default Slave Select pin (Digital pin 10) on Arduino UNO R3 for SPI communication?

Currently I am working on an Arduino based project. My project require interfacing 6 servo motors and an SD card module to my Arduino UNO. The problem is that I need all the six PWM pins for six ...
0
votes
1answer
42 views

Controlling 5V PWM Fan with Potentiometer

Alright so I wanted to make myself a Deskfan using Arduino and a potentiometer. The reason for using arduino is that I want to display the current temperatur and the fan speed either through rpm or ...
-2
votes
1answer
33 views

Why do COM port numbers between Arduino and Processing not match? [closed]

I have a Processing program that reads data sent to the serial port by an Arduino. When I go to device manager it shows that the Arduino is plugged into COM 4, however in order to get Processing to ...