All Questions

0
votes
0answers
2 views

http.POST is not sending data to local web page

so i am using a nodeMCU to send data to my local web page developed using Spring boot but when i run the code i don't get an error the esp8266 connects to wifi but i don't get anything on my spring ...
-1
votes
2answers
37 views

How to prevent modify library of arduino?

For some reasons of security, I created library for everybody to use, but I don't want people change my library, cause it make device not work. I search around but still not working. Do I need to set ...
0
votes
0answers
6 views

How can I reset servo position?

When I do myServo.write(0) It isn't straight, I want it to be straight but it is at about a 45 degree angle anyone know how to reset the position with arduino to make other positions 0 and making ...
0
votes
2answers
27 views

Update time in RTC over I2c fails

I am communicating two arduinos using the I2C protocol and sending from the slave to the master the integer value of UTC to update the time in the RTC module. When the master receives the UTC value ...
1
vote
0answers
697 views

Interrupt for traffic light

I have mini project which is Emergency Traffic Light for Ambulance, police etc. What I am try to do is when emergency traffic light go through first sensor 1 (in this code I just using button, “SA”), ...
0
votes
0answers
10 views

Controlling UC1638 Graphical LCD screen (C, with Arduino)

I am using Arduino Uno, trying to control LCD screen type UC1638 (240x128 monochrome) I want to fillup the screen in black). Searching up the internet I ended up using this code (written in C): /* ...
0
votes
1answer
25 views

Dynamic memory 'new' (of an overridden class) call affects SRAM memory

I have made a quite large program (not executed at an Arduino lately). However, if I compile with the next fragment: void LightSetupClass::CreateFixtures() { for (fixture_number_t fixtureNumber =...
0
votes
0answers
47 views

Is the Nano USB-serial supported with native drivers on MacOs? [on hold]

I'm making a peripheral using a Nano clone. All of those seem to use the CH34x serial chip. I'd like to believe that a naive user can just plug my device in and the OS will either have or find the ...
0
votes
0answers
13 views

Multiple libraries were found for “WiFiClient.h” using nodemcu

I am trying to send HTTP requests from nodemcu so I started by uploading the esp8266 library but when I run the following code #include <ESP8266HTTPClient.h> #include <ESP8266WiFi.h> ...
3
votes
1answer
26 views

writting to buffer from serial input

Can some one explain this behaviour please, i have the following code byte buffer[512]; byte block; byte len; Serial.setTimeout(60000L) ; // wait until 20 seconds for input from serial ...
1
vote
0answers
2k views

Sending data from Arduino w/HM10 to relay board with hm12

It all started when I tried connecting an hm10-nano to a relay board which is Bluetooth enabled. Here is my nano with the hm10 module: And here is the relay board's BT module, which looks like an ...
1
vote
1answer
56 views

Using Arduino as ISP and SoftwareSerial at the same time

I'm trying to use my Arduino Uno as an ISP to program an ATTiny85 and at the same time check my board by using the SoftwareSerial library to output the values I'm getting from my sensor. Is this ...
1
vote
1answer
24 views

Arduino Timer with increase time button

I have an Arduino project to do, which requires a countdown timer(which I've already done). I connected a push button, and when I press that button I need it to increase my countdown timer by +10 ...
0
votes
0answers
16 views

Esp8266 module with 5v

My esp8266 module clearly says vcc which indicate 5v but i have read that es8266 only work with 3v3 here are the images for my module esp8266 module image
0
votes
0answers
10 views

Maximum voltage supplied on a port set as output

I've 1 port set as output on the ESP32. On HIGH, there's 5V on the port . It's working fine for several months now, but I'm wondering: what is the maximum voltage on a port set as output? I can ...
0
votes
1answer
27 views

Flashing ESP8266 ESP-12E/12F

I'm pretty new to Arduino programming and i'm trying to connect this ESP8266 module to my FTDI programmer but constantly getting this error on my ARDUINO IDE: esptool.FatalError: Failed to connect to ...
0
votes
0answers
22 views

i2c slave write to ARM powered device master

I want to communicate to an ARM microprocessor via I2C protocol (Multitech mDot, which uses Mbed platform). I successfully receive data from it (and got it displayed on Arduino's serial monitor), but ...
0
votes
0answers
18 views

LED Strips - Data Noise Over Long Distance Between Controller and First Strip [on hold]

Please refer to the above picture. The black line is the ground wire and the green line is the wire carrying data. First Question In regards to data noise/interference, can the output ground wire ...
0
votes
0answers
7 views

What is “tCAN” in codes of CAN bus? [on hold]

I'm new to Arduino and CAN bus. I'm studying some code examples which contain "tCAN message". My guess it defines a class for of CAN messages. I did a lot of search but found no information on it ...
1
vote
1answer
285 views

SOLVED: Strange phenomenon with avrdude: stk500v2_ReceiveMessage(): timeout only with ATmega250 on windows 7x64

I know this problem has been reported multiple times but in my case I think there is a different light on it. My desktop is a w7x64 box and I also have a notebook with w10. Both system have the ...
0
votes
0answers
15 views

i have a problem with mdns i'm using an ESP8266

I am working on a project on which I have to drive a DC 12V motor. I use an ESP8266 I manage to manage my engine remotely but my only problem is the mdns I use the mdns but it does not work. when I ...
-1
votes
1answer
26 views

expected unidentified id before 'if" [on hold]

#include <iostream> using namespace std; char board[3][3]={{'1','2','3'},{'4','5','6'},{'7','8','9'}}; char turn='X'; int draw=0; int row,column; void display_board() { system("cls"); ...
10
votes
4answers
2k views

Getting a truly random number in Arduino

What is the best method to get a truly (as opposed to pseudo) random number in Arduino, or at least the best possible approximation? From my understanding, the function randomSeed(analogRead(x)) it's ...
1
vote
1answer
143 views

Threshold to wake up signal

I have a sketch to put to sleep and wake up an Arduino Pro Mini 5V, but the problem is that sometimes when it is moved fast it wakes up itself, thing that I do not want. I have it configure to be ...
0
votes
1answer
26 views

AC Voltage Sensing using Arduino Uno

Is it possible to sense AC Voltage using analog input for Arduino Uno or can it only read DC? I mean I've tried connecting an AC voltage source to analog and I'm reading some numbers. However, I don'...
0
votes
1answer
11 views

Possible to have different torque levels on MG966R servo with Rotary Potentiometer?

I want to apologise first and foremost, and say that I am very new to Arduinos! I wanted to control the torque on a MG966R servo so that I can separate it into 4 different torque levels. I read that ...
0
votes
0answers
14 views

Microsd card PCB circuit designing [migrated]

I am trying to develop a microSD card module myself. My microSD card module is working at 3.3V and my microcontroller is operating at 1.8V. I have therefore used TXB0104 voltage level shifter to ...
0
votes
0answers
14 views

ESP32 Connecting to any available network? [on hold]

I am using an ESP32 to connect to a local WiFi hotspot on my computer. I am using the following code - const char* ssid = "yourNetworkName"; const char* password = "yourNetworkPass"; WiFi.begin(...
0
votes
1answer
33 views

Memory usage in AnalogBinLogger of SdFat library

The AnalogBinLogger.ino file of SdFat library says the following: Each 512 byte data block in the file has a four byte header followed by up to 508 bytes of data. (508 values in 8-bit mode or 254 ...
0
votes
0answers
29 views

Clap switch lamp [on hold]

I have previously uploaded a code to my arduino uno and it worked. The project is a clap switch lamp ( sound sensor detects sound and lights up the led, if there is another sound led will go out). ...
1
vote
1answer
25 views

Serial Communication between arduino and nodeMCU

I am trying to connect a nodeMCU to arduino mega using serial communication so that i can read data from firebase. I have put the following code on the NODEMCU. #include<SoftwareSerial.h> //...
0
votes
1answer
28 views

why arduino can not write to server?

i write a code for Arduino + SIM800 for connecting to server. but it don't work! SerialGsm.println("AT+CIPSEND=63\r\n"); delay( 1000 ); receive_message(); SerialGsm.print( "GET http://sasasas.ir.ir/...
2
votes
1answer
26 views

Which sources of randomness are available? [duplicate]

I need a souce of randomness to generate a seed to pass to randomSeed. Where can I get this randomness from? Well, I hear I can read random noise from an unconnected pin. But I need to connect 9 ...
-2
votes
1answer
42 views

PIR sensor and hex inverter open collector

the M7404 Hex inverter is used to send an active low signal from a PIR sensor to a microcntroller pin However the reset is being constantly sent some signal keeping it set to on. You can tell because ...
0
votes
0answers
18 views

Elegoo Uno R3 Shorting out after wire is plugged into 5v

I'm pretty new to Microcontrollers and I have mostly just a programming background. What I am trying to build is a device that uses the ultrasonic sensor to turn a LED on/off using the HC-05 ...
1
vote
1answer
462 views

rf522 version 0x12

I bought a bunch of the common RC522 boards from some Aliexpress vendor. They (I tried multiple) seem to work at the register read-write level, but they don't seem to execute commands, much less ...
1
vote
0answers
1k views

Arduino Leonardo isn't detected by Linux Mint on serial port /dev/ttyACM0

I'm working on Linux Mint 18 Sarah (earlier Ubuntu 16.04 LTS) system. I've installed Arduino IDE using command sudo apt-get install arduino and I've added me dialout group using sudo usermod -aG ...
0
votes
0answers
16 views

Confused in Voice or Speech recognition [on hold]

i'm doing a project to voice control some stuff in my house like lights , but i'm confused in choosing between elechouse module or EasyVR 3.0 to recognize my voice commands. I want my project to ...
0
votes
0answers
36 views

Why the PWM blinking the LED?

The LED on PWM pin is blinking while turning it on! Here's the code: int onHourONE = 11; int onMinuteONE = 00; int offHourONE = 23; int offMinuteONE = 00; unsigned long PWMdelay = 236; int PWMstatus =...
0
votes
0answers
15 views

“exit status 1 Error compiling for board Arduino/Genuino Uno.” Error when verifying code [on hold]

So I have been trying to learn use the Arduino LED Matrix, however I have faced a few roadblocks. I get a error everytime i verify/upload the code.The solutions on other forums seem to be on the lines ...
1
vote
1answer
49 views

Problem with passing string pointer from child to parent

I am trying to pass a pointer to a const char * from a child to its parent, but I am clearly not understanding how to do this correctly. Here is the code which contains three classes: 1) parent 2) ...
0
votes
3answers
256 views

How to set CS pin on Beetle BLE/Bluno Beetle to Adafruit SD Card Breakout - Initialization Failed!

Hi I have a Beetle BLE (https://www.dfrobot.com/wiki/index.php/Bluno_Beetle_SKU:DFR0339) and I am trying to connect an Adafruit MicroSD card breakout board+ (https://www.adafruit.com/product/254) via ...
1
vote
0answers
45 views

how does c++ understand which function must to use?

in this code: void AdptSendReply(const char* str) { string s(strlen(str) + 2); s = str; AdptSendReply(s); } void AdptSendReply(const string& str) { string s(str.length() + 2);...
0
votes
1answer
26 views

Rounding float number

I want to enable user to change the duration of PWM from 0 to 255, the number should be in minute and increase/decrease with two push buttons. (X) x 255 / 60000 = minute In above example each time ...
0
votes
2answers
53 views

ESP12E Soft WDT reset stack trace leads to libraries

Im using ESP12E DevKit v2 (esp8266 wifi module) board for controlling relays and displaying DHT22 temp,humidity on web server. It runs smoothly when the web client is closed but when i leave the ...
0
votes
0answers
15 views

Connecting GoPro to Raspberry Pi with Bluetooth [on hold]

Is it possible to send commands to the GoPro and receive video/photos with a raspberry pi over Bluetooth?
0
votes
1answer
20 views

Libraries not included correctly

I stumbled upon the following unexpected behaviour and am curious about its cause. header.h: #include <Time.h> [...] main.ino: #include "header.h" #include <Time.h> [...] My code is ...
1
vote
1answer
57 views

analogRead() output oscillates even though the pin is grounded

I'm using Arduino Micro to read from 5 flex sensors and display the corresponding angles to the Serial monitor. I am currently having quite some problems with the oscillating values I am getting from ...
0
votes
1answer
35 views

Arduino OSX Mojave - Serial port only shows sometimes

I've found lots of issues about serial ports not showing up at all, but none about what I'm experiencing. Sometimes I can see my Arduino Mega 2560 in the ports list, and sometimes I can't. I've tried ...
1
vote
2answers
52 views

Arduino Nano LED not working

I am just starting with Arduino and was trying to make the LED example work. I changed the script as follows to keep the LED on: #define LED_PIN 12 #define LED_RX_SIG LED_BUILTIN void setup() { // ...

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