All Questions

1
vote
3answers
9k views

Problems with using example code for Wi-Fi shield (arduino)

I have problems with the Wi-Fi shield example code. #include <SPI.h> #include <WiFi.h> char ssid[] = "*****"; // your network SSID (name) char pass[] = "*****"; // your ...
1
vote
1answer
541 views

Arduino 1 can somehow support 32-bit audio? [closed]

I wanted to take the audio from a device such as the PC, insert it through different ADC in arduino, processing them with DSP and DAC REnter all through to the other speakers, reading here and there ...
3
votes
1answer
267 views

Adding devices makes I2C read 0

I'm using an Arduino Due with a logic level converter to interface with two different 5v sensors via I2C. Being of poor quality, these sensors have no data sheet. When either one of these sensors is ...
4
votes
1answer
17k views

Reverse turning of Stepper motor

I have a stepper motor connected to my Arduino like this using the ULN2003A Darlington Array: (Ignore the potentiometer) And I have programmed it with the following code: #include <Stepper.h> ...
1
vote
1answer
68 views

Simple Script controlled by Raspberry not working

I can't figure out why the next script is not working. I have attached the Arduino to one USB port of the raspberry pi, in which I've installed pyserial. I just want to turn off/on a led depending of ...
2
votes
2answers
2k views

Sketches not uploading to Micro from Ubuntu 14.04

I recently bought an Arduino Micro to see what all the fuss was about and I figured I'd use it with Ubuntu on an older Dell Latitude. I was able to install all of the files using some tutorials but I ...
9
votes
3answers
2k views

How to write makefile-compatible sketches?

I'd like to write my sketches so that I can either build/upload them using the Arduino IDE, or optionally using GCC and a makefile. I know about including the function declarations at the top, but is ...
0
votes
3answers
2k views

IR controlled light dimmer

I am doing a project on Arduino controlled light dimmer circuit... I have a separate circuit for zero crossing detector and IR receiver but when I am combining both of them in arduino then my IR ...
11
votes
2answers
7k views

Getting the contacts/ storing contacts to SIM card

I have the GSM shield and is there any ways to get the stored contacts on the SIM card? It seems that the GSM library does not support writing data onto/ reading data from the SIM card? My aim is to ...
1
vote
1answer
2k views

Can Arduino Mega2560 Use this 24VDC Relay?

Can a Arduino MEGA 2560 R3 provide enough current out of its pin to activate the Songle srd-24vdc-sl-c relay? Will powering the Arduino with an external power supply help?
2
votes
0answers
2k views

Sending information through Bluetooth 4.0 (LE) with Tinyduino

My task is to measure distances quite rapidly and send the data to a computer. I need to do it with the following equipment: Tinyduino Processor board Tinyduino Bluetooth LE shield Tinyduino Cell ...
3
votes
1answer
773 views

Arduino Uno + Ardumoto + BT robot works from USB but not from baterries

My Arduino UNO board is part of a small robot that works when connected to the laptop by USB but it does not when plugged to the batteries. The baterries plug seems okay, it outputs 7.8 V. My UNO is ...
7
votes
1answer
1k views

How can the Arduino Uno support up to 12 servos if it only has 6 digital PWM pins?

According to this: The Servo library supports up to 12 motors on most Arduino boards and 48 on the Arduino Mega. On boards other than the Mega, use of the library disables analogWrite() (PWM) ...
1
vote
2answers
1k views

Multiple definition of '__vector_36' (intterupts)

I'm having some conflicts between the core HardwareSerial.cpp and an external DMX library. For DMX I'm using the Four Universes DMX 512 Library. Using the library standalone, it all works perfectly. ...
2
votes
2answers
579 views

Is it possible to transmit Longitude and Latitude via RF433MHz?

I want to make a drone project, and to that I will use arduino as the platform. My plane is to use a Play Station controller to control the Drone in the air. In addition to that I want to connect a ...
5
votes
2answers
512 views

Understanding the relationship of Pulse and Stepper RPM

This may be a better question for the Physics StackExchange so tell me if I should move the question. I have a pretty simple script that I'm using to control the RPM of my stepper motor: void loop(){...
1
vote
1answer
307 views

Larger NFC antenna? [closed]

Goal: I would like to be able to transfer some information to an Arduino Uno board via an NFC shield/antenna. The situation requires that the NFC tag may potentially hit anywhere within a circular ...
2
votes
2answers
3k views

Which motor (type) to use for an arduino controlled magnetic stirrer?

I am in the process of building my own sous vide machine and like to replace the pump typically found in most commercial machines with a magnetic stirrer unit. I figured the easiest way would be to ...
2
votes
2answers
2k views

Default value of global variables is not set

I am tracking a bug in the Marlin source code. Background Just for those who is not familiar with Reprap 3D printer and G-code: Marlin is firmware that controls a RepRap 3D printer. It receives G-...
10
votes
3answers
36k views

How do I use RFID-RC522 with an Arduino?

I am working on a project for my local Makerspace, we have limited budget so I was hoping to use the RFID-RC522 el'cheap'o RFID/NFC readers on eBay, I received a couple of SPI based boards, they work, ...
1
vote
0answers
79 views

is it possible to backup an uploaded program? [duplicate]

I have a cute robot built on Arduino Uno and Ardumoto, and I am trying to reverse engineer it first, and to add some new sensors afterwards. I am stuck at how to deal with its program. I don't have ...
1
vote
1answer
839 views

Set up an Arduino Cellular Shield SM5100B

I'm trying to set up an Arduino Cellular Shield SM5100B to send SMS. My setup is: Arduino UNO R2 SM5100B "Movistar" SIM Card (Chile) I've uploaded a code similar to the one described here, but ...
2
votes
1answer
307 views

XBee, external libraries and passing structures as arguments

I have very weird problem with a library I am creating. The library will be used to communicate between Arduino modules using XBee Series 1 modules. Library is very simple wrapper library around ...
9
votes
2answers
929 views

RFID/NFC (13.56 MHz), is it possible to send raw bytes and receive response?

I'm trying to implement a card reader (i.e. credit cards) for shopping purposes, and AFAIK those cards are ISO 14443-A compliant (Mifare Classic 1K). I already made an Android app that can send custom ...
4
votes
2answers
36k views

Servo won't stop rotating

I have an Arduino Uno R3 board and after some time not in use it seems to have corrupted. My code is below, basically I want to rotate a servo 90 degrees every 12 hours but as soon as I plug it in the ...
6
votes
2answers
3k views

Level detection of 3.3V from 5V arduino

A quick question about microcontroller digital level on I/O pins. I have a photo interrupter which is powered at 3.3V which is interfaced to Arduino UNO running at 5V. For microcontroller to detect ...
4
votes
2answers
1k views

How can I connect the Tamiya double gearbox to Arduino Uno?

I'm working on building my first robot. this is my first foray into DIY electronics. I already have an Arduino Uno, and I have ordered the Tamiya double gearbox here. My goal is to control the gearbox ...
10
votes
1answer
1k views

Understanding the compilation/linking/upload process (so I don't have to use the IDE)

I have started to play with and arduino UNO quite recently (without any prior experience with micro-controllers). I would like to use emacs instead of the IDE, and I'd also like to know what the IDE ...
1
vote
1answer
339 views

Connect Arduino with fischertechnik TX Controller

Is it possible to cinnect the Arduino with a fischertechnik TX Controller? Maybe with I²C, but i want to use I²C for something else on the arduino. So are there multiple I²C Ports on the Arduino (I ...
-1
votes
2answers
2k views

Arduino Mega & WiFi Shield; why web server every time says my A7 pin reads 0V?

I have got Arduino Mega 2560, Arduino WiFi Shield and resistor 1.5K. Now PWM 2 is attached to the resistor then attached GND. 5V is attached between PWM2 and resistor's up point. I want to read the ...
7
votes
3answers
5k views

Manchester Library Won't Compile for Attiny85

I am creating a wireless sensor using an Attiny85. I want to send the data to an arduino uno, so I purchased the 315mhz rf link kit from spark fun. Since the Attiny85 does not have a TX I decided to ...
4
votes
1answer
124 views

How to use components that don't have a shield?

I recently started messing around with an Arduino and I have made a few "gadgets" using shields. I then wondered how I would go about using things I can't find shields for. One specific thing I want ...
2
votes
1answer
3k views

How to test the sleep / enable function of Stepper Driver?

I am currently using an Arduino Mega 2560 to run this stepper motor driver (Big Easy Driver, ROB-11876 from sparkfun) https://www.sparkfun.com/products/11876. I am trying to use the sleep or enable ...
4
votes
6answers
12k views

Detect and stream if a chair is occupied

I am planning to build a device able to detect and tell a server via Wi-Fi if a chair is occupied. How would you do it? And how cheap do you think the device could be?
2
votes
2answers
802 views

Matching Baud Rates

So I am working on speeding up a nixie tube speedometer, in this question: , but this brought up another question. Would having matching baud rates for multiple external devices speed up processes. ...
4
votes
1answer
2k views

Check contents of buffer after serial read

I would like to test the contents of data received over a serial connection. In my loop() I store the data in bffr; and afterwards I would like to test to see if there are some predefined words in it. ...
4
votes
1answer
112 views

SeeedDuino/Grove and the story of not being able to upload programs

I am new to the arduino world and wanted to start playing with the micro controllers, I am a .NET developer by trade so not completely new to this kind of world. I purchased a seeedduino v3 and a ...
1
vote
2answers
218 views

Arduino Yún console clear

I'm having a problem. I want to clear the screen on the connected console. And after the clear, I want to rerun my code. But I can't seem to figure out how to do it. Below is some part of the code: #...
6
votes
5answers
9k views

Simultanous read and read/write on two serial connections

At the moment I'm using two softserials to connect to a GPS and an GSM module. It seems not possible to have two open software-serials. So I was looking for an solution After the initial-setup, the ...
3
votes
1answer
152 views

Which voltage regulator should I use? [closed]

A friend and I are working on building a smartwatch on a budget, so it’s a (very) low power project, but we are currently having a problem with the power supplying. We already chose this board, ...
5
votes
3answers
4k views

How can I convert Arduino String to C string type?

I got a String which as I understand is an Arduino object, and got some C++ code: #include <Wire.h> #include <LiquidCrystal_I2C.h> #include <string.h> LiquidCrystal_I2C lcd(0x20,...
3
votes
1answer
93 views

Pull Chain Switch

I'm a bit new to electronics/Arduino projects, so am looking for some help on some wiring needed for a project involving this Pull Chain: http://proto-pic.co.uk/pull-chain-switch/ The chain works ...
1
vote
1answer
5k views

How to control Keyboard inputs using arduino(serial monitor) and python keyboard libraries?

I am able to control my monitor and most other applications by giving serial input to python through arduino. Arduino code: void setup() { pinMode(2, INPUT); pinMode(3, INPUT); pinMode(4, ...
6
votes
2answers
7k views

Control/count rotations of a DC motor

Using an Arduino and an L293D IC, can I control the number of rotations a DC motor makes? Or can I only control the direction and speed of the motor? I purchased a two-wheeled robot platform to learn ...
2
votes
1answer
2k views

Interference at digital input (UNO) [duplicate]

I was trying out a basic button tutorial on my new Arduino UNO. But for some reason, the Arduino was detecting the button as on (pressed) even when it was off (unpressed). After some experimentation, ...
2
votes
1answer
239 views

Arduino Uno and Leonardo SPI clock can't be measured

I want to measure the SPI clock (pin 13) using the Arduino example code for the SPI library (very simple example). Basically independent from the loop function, the clock should be fired continuously. ...
10
votes
1answer
14k views

Can I write to Flash Memory using PROGMEM?

On the documentation of Arduino, I quote: http://playground.arduino.cc/Learning/Memory Note: Flash (PROGMEM) memory can only be populated at program burn time. You can’t change > the values in ...
4
votes
3answers
3k views

Super slow serial (UART) communication on Arduino

I am using this device for my Arduino that connects to the OBD-II port of my car to get various information such as speed, rpm, etc. I am using this for a digital Nixie tube speedometer using the ...
1
vote
1answer
227 views

How to catch the Enter key received by Bluetooth?

I got some code to receive characters from Bluetooth and code and print it back to the LCD display. However, want to detect the Enter character to be the input signal, in other words, not to print ...
2
votes
2answers
9k views

A waterproof Chlorine Sensor

Does anyone know where I can find a Chlorine Sensor to use with the Arduino? It would need to be water proof. I've googled, but I couldn't find anything. EDIT Requirements: relatively inexpensive (...

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