All Questions

0
votes
0answers
12 views

Reaction timer with interrupts

I've written this code for a reaction timer game. The LED is supposed to come on and blink when the game starts before going off and then lighting up again after a certain time. The user must then ...
0
votes
0answers
11 views

Mqtt not subscribe on topic that's converted from String to char array

I am still not sure what should be the exact Title for this question, because I don't know where the problem is. I am using #include <MQTTClient.h> mqtt library to subscribe on a topic. This ...
0
votes
0answers
3 views

Opencv Gtk2 Gtk3 Compability Problem [migrated]

I am using opencv-3.4.2. I want to use opencv for image processing and gtk3 for displying controls. I finished the ui using gtk3. But after I put in the gtk code inside my main function. Every time I ...
0
votes
0answers
9 views

HD44780 display incorrectly black-on-blue instead of white-on-blue

I have a generic HD44780 compatible 16x2 LCD display, with an already soldered on PCF8574 module. Its backlight is blue, and the characters are supposed to be white (on blue). It is connected to a ...
-1
votes
0answers
14 views

Have a few questions regarding BNO055

To reuse a calibration profile, do I need to read the calibrated offset values, store them and then hardcode the registers to those values on bootup? Do I need to check the calibration status register ...
0
votes
0answers
8 views

Read SNMP OID values with Arduino

I wish to read SNMP predefined OID values from other devices, can it be done with Arduino? I searched all over the internet for the past 2 weeks about Arduino with SNMP and found a lot of great ...
0
votes
0answers
18 views

ESP8266 WiFiClient Slow Over LocalHost

Appears to be something to with Apache configuration, swapping to Nginx solved my issue. I'm getting slow responses when using localhost with a NODEMCU 1.0 and esp8266 WiFi library. If I GET a PHP ...
0
votes
1answer
14 views

Compare incoming message from ESP8266

If there's one thing I never managed to do: it's comparing strings. So I have the incoming message saved here String Message2 = IClient[i].readStringUntil('\n'); And every time I try to compare it ...
0
votes
1answer
18 views

Correct Pins for Nodemcu 8266

I am building a small electronic project, and I am incorporating module nodeMcU 8266 in a box. I would like to know which pins are for "flash" and for "reset" I know there are 2 buttons on the module ...
0
votes
1answer
15 views

Verifiy NTP server update - at start

I have function to start an NTP service, right after obtaining wifi connection ( using ESP8266 board ). from time to time, I get an error saying date and time is01-01-1970... which I assume is due to ...
0
votes
0answers
12 views

Closed Loop Stepper Motor Control with ACE128 Absolute Rotary Encoder

I am using a 1.8 Resolution Stepper Motor controlled by a L298N driver and Arduino Mega. I have attached the ACE 128 Absolute encoder to the motor to use it as a closed loop system. The idea is for ...
0
votes
0answers
10 views

Ultrasonic,pir,gas mq2 sensor using Arduino in one code? [duplicate]

I have a three sensors codes but its are separately. I don't have knowledge of these code merg in single one code
0
votes
1answer
21 views

Control Air Pump Depending on Pressure Sensor

I am working with an Arduino Mega, a 12V micro air pump, and a MP3V5050 air pressure sensor. The sensor outputs an analog voltage depending on the pressure reading in an inflatable member. I'd like to ...
0
votes
0answers
13 views

How to trigger a link using esp8266 in GET method?

I am trying to send a sms using a api called fast2sms . Notifications will be sent by triggering that link .I am new to this wifi module and I am not understanding how to trigger that link.
0
votes
0answers
9 views

Question about write-speed to a micro-SD Card on Adafruit Feather M0

I am working on a project and am having difficulty maximizing how fast we are able to write data to our micro-SD card. Our current setup is an Adafruit Feather M0 with a Class 10 Sandisk Ultra. We are ...
0
votes
1answer
22 views

Program Upload Loading problem

Please help me about this program uploading problem. Arduino: 1.6.13 (Windows 10), Board: "Arduino Nano, ATmega328P" Sketch uses 930 bytes (3%) of program storage space. Maximum is 30,720 bytes. ...
0
votes
0answers
20 views

Webserver on Arduino Mega with Ethernet Shield

I am working with an official Arduino Mega. I have mounted an officiel Ethernet Shield rev 2. Everything works great, i have wrote a very basic webserver. I wanted to host a bootstrap css file on my ...
0
votes
0answers
13 views

Did not found fingerprint sensor even if the sensor light is on [on hold]

I'm using Arduino Uno, the wirings are Black - GND Red - 5V White (RX) - TX Yellow (TX) - RX The wires are in bundle so the white one and yellow one is on RX and TX respectively. Red wire is on ...
0
votes
0answers
8 views

my problem is when configuring the XBee with the arduino

I tried configuring the xBee using arduino but it always fails, I downloaded the X-CTU to configure it but it doesn't recognize my XBee. Knowing I am using XBee pro S2B it shows me the following: ...
0
votes
0answers
14 views

Arduino based Bluetooth-USB pass through device

I new to this particular StackExchange. I am looking for guidance on whether it would be possible to create a device using an Arduino Uno to replace a USB serial cable currently being used to pass ...
0
votes
0answers
22 views

Smart shopping system project [on hold]

I am doing smart shopping system project. I can added and remove product using RFID in ARDUINO. I need ur help to show all added products in lcd by pressing a push button
0
votes
0answers
12 views

difference between v2 and v3 in terms of connecting with firebase [on hold]

v2 is perfectly working when sending data on firebase but it doesnot work when sending a data through v3. can anyone suggest me the valid difference between v2 and v3 which is responsible for sending ...
0
votes
1answer
38 views

Any idea why my LED fails to operate with the if statement

I have tried several workarounds without success. #include <LiquidCrystal.h> float tempC; int tempPin = 0;// BS E D4 D5 D6 D7 int buzzer = 4; int LED =2; LiquidCrystal lcd(7, 8, 9, 10, 11, 12);...
0
votes
1answer
15 views

WifiClient and aREST on esp32 - loop until new instructions recieved?

I've created a simple sketch for an esp32 that hosts a REST API that can be accessed via HTTP. Based on the instructions received from the client, the esp32 controls some neopixels with some various ...
0
votes
0answers
40 views

Need help with DAC to show more than one output with SPI (stuck and need help please)

I want to take 2 different outputs from my DAC from void setDacOutput function (and it should be switching with/like the timer for both outputs. One output of 2.9375V for 0.9ms from ISR if statement ...
-1
votes
1answer
27 views

Simple code to define pins used for Shift Register control - Error: a function-definition is not allowed here before '{' token

I'm simply trying to light up some pins on a customized circuit board via Arduino. My code below has the seemingly common error "a function-definition is not allowed here before '{' token". I've ...
0
votes
0answers
26 views

How to measure multiple voltages (Thermocoupes)

How would one measure many (20-100) small voltages in the 0-80mV range with an Arduino? I will need to amplify them and put them into the ADC. But i also need to switch between them. I want to ...
-1
votes
0answers
27 views

TRRS breakout board connection to Arduino Nano

Is there any way to connect a TRRS breakout board to an Arduino Nano? The audio signal is going to be coming from my laptop which is an analog signal
0
votes
1answer
24 views

How to use 2 serial port when WifiEsp library uses one of both

I try without success to receive datas from DataPort and transmit them to my computer via WifiPort, using ESP8266 wifi module. Each second, serial datas income on DataPort from another device. ...
-1
votes
1answer
38 views

Parsing data in arduino?

I just started working with Arduino and in my project I am trying to achieve the COMM between two Arduino using HC-05 in master and slave mode respectively, I configured it all successfully. Now I ...
0
votes
0answers
13 views

Arduino - State of Charge (SOC) Measurement [on hold]

I am doing a University Project which requires determining the State of Charge (SOC) of a battery. The usage of battery voltage for approximate determination would reduce the accuracy. So I am ...
0
votes
1answer
39 views

my LM35 temperature sensor gives weird measurements,

Board: esp32 I know my wiring is correct because I get data from the sensor, but the data is a bit weird. At 22 celcius I get 140, even though if I do the voltage calculation (* 0.473372) it still ...
0
votes
0answers
15 views

Nrf24l01 interfacing with arduino [on hold]

Can we calculate the distance between 2 nrf24l01 modules and work accordingly..? I have tried the testcarrier function but it didn't give me any values
0
votes
1answer
19 views

Reading NFC card (PN532) with Arduino Uno

I am trying to detect a RFID card using the NFC-PN532 module and Adafruit_PN532 library. Initialization code:- #include <Adafruit_PN532.h> #include <Wire.h> #define SCK (13) #define ...
1
vote
1answer
30 views

Force TCNT to stay below OCRxA on ATmega328P

I'm using a timer and the TIMERx_COMPA ISR to generate a signal in "the background". This ISR is triggered when the timer reaches a certain value (OCRxA), which in turn can be changed by the user. ...
0
votes
1answer
30 views

problem with connect arduino with atmega32

i need to connect atmega32 as master and arduino as a slave so i write this code and i don't know where is the wrong #include <Wire.h> int led1= 13; int led2 = 12; int x =0 ; void setup() { ...
0
votes
1answer
36 views

Switch Statement stuck in loop

I am writing a code for a user to enter a 4 digit pin, then use this pin later to unlock a box. The loop is stuck between the "ready to unlock box" and "enter pin" it just keeps flipping between ...
1
vote
1answer
49 views

16 X 2 LCD display blank with Arduino Uno

So I am following this tutorial to make my arduino display hello world and millis(), I got it to work for a minute, but then it stopped updating the milliseconds, and when I pushed the reset button it ...
-1
votes
0answers
21 views

3 button password sequence [duplicate]

im trying to make an led turn on after a sequence of buttons is pressed (1, 2, 3, 3, 1) but after i press one button the incorrect led comes on straight away and im not really sure why. im not very ...
0
votes
1answer
23 views

Run website / Javascript game from a Arduino UNO device?

I apologise if this is a dumb question, but I'm trying to find information on whether or not this is possible. I'd like to build a arcade machine to play my custom Javascript 2D game. The game ...
0
votes
1answer
22 views

About possibility of implementing kalman filter on atmega32

I have searched on the internet on how to get Euler angels from IMU measurements,I found that kalman filter and mahony filter are used...kalman filter has a drawback of complex computations,but mahony ...
0
votes
1answer
50 views

Please explain the void loop() section of the sketch

#include <VirtualWire.h> int PWMB = 5; //Speed control void setup(){ Serial.begin(9600); //receiver setup vw_set_rx_pin(2); vw_set_ptt_inverted(true); vw_setup(2000); ...
1
vote
1answer
35 views

Im trying to get a 3 button password sequence working

I'm trying get a password system working that when you click 3 buttons in a certain order (1, 2, 3, 3, 1) then an LED will light up. But as I'm going to implement this into a larger code I can't just ...
0
votes
0answers
24 views

6 Pin Relay with electricity [on hold]

i have this 6 pin relay, i want to make simple project with "RIP Sensor" and "Relay" so when sensor detects somebody it automaticlly turn on the light Thanks.
0
votes
1answer
36 views

invalid conversion from 'uint16_t* error when creating an array of uint16_t items

I'd like to create an array of remote control codes provided by the raw read feature of the irlib2 library. irlib2 provides the following uint16t arrays using the following format: #define ...
-1
votes
1answer
37 views

Replace Arduino bootloader

My Arduino board is malfunctioning in its bootloading and I thought weather I can overwrite the previous bootloader on the atmega. I mean to ask than can I simply reinstall bootloader on a chip that ...
0
votes
0answers
18 views

Bluetooth gamepad via Adafruit Feather M0 Bluefruit BLE

I'm trying to build a Bluetooth-enabled gamepad out of an old Playstation 1 controller, using an Adafruit Feather M0 Bluefruit BLE. I've programmed the board as a Keyboard HID and everything works: ...
0
votes
0answers
15 views

How o calibrate ZE11-C2H4 sensor with Arduino Uno? [on hold]

I want to calibrate ZE11-C2H4 with Arduino?
0
votes
0answers
14 views

PLC with Arduino UNO [duplicate]

In my current project I have to communicate with 10 different devices with PLC. PLC is the master. When input comes from PLC to a device, the Arduino controller through RS485, I want to check the ...
-2
votes
1answer
39 views

What should the cut-off frequency be?

To convert a PWM signal to a DC voltage it must be filtered with a low pass filter. How can you know which cut-off frequency should be used and how do you calculate the values for the resistor and ...

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