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Questions tagged [arduino-uno]

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

4
votes
1answer
594 views

Can a PC connect to an Arduino for serial communication without installing the entire dev kit?

I'd like to send a prototype board to a friend pre-programmed and wired. Ideally they should just need to plug in the USB and connect to it over a serial COM port. With another laptop I used for ...
1
vote
1answer
763 views

Unable to read text file from server

I saw the Web client Example , In the example, the server connection is initialized in setup(). But I want the server to update the text file every time. So, I need the server connection to be in ...
1
vote
1answer
321 views

Detecting ball moving between IR pair and handling ambient light changes

I plan to use the SEN-00241 IR Emitter and Detector pair to detect a ping pong ball moving fast between them. I understand I could watch for voltage changes to detect this passing object, however how ...
0
votes
1answer
653 views

DC-DC converter with Arduino not working

I've got a program running on the Arduino that is supposed to turn on and off a pump. currently, I am outputting the reads of the components that need to be read and it shows when the port (port 13) ...
-2
votes
1answer
1k views

Cheapest way to connect android device to arduino wirelessly

I'm building a simple RC car which I want to control using android phone. The phone has bluetooth and Wi-Fi. My questions is what will be the cheapest way to connect the two devices at about 50-120m ...
6
votes
2answers
2k views

Use Higher Resistance Than Instructed in a Circuit

I'm following the "Get Started with Arduino" Guidebook, and I'm at the part where pulse width modulation (PWM) is discussed. The instructions say to create a simple circuit with a breadboard, red ...
-1
votes
1answer
502 views

How to update a text file dynamically

I have Two Arduinos, One with the help of sensors it will dynamically updates in to my server database. Other Arduino, reads the stored contents from the server database and sends sms to phones. Now, ...
6
votes
2answers
1k views

Convert a Bitstring into an integer value

I have got a String filled up with 0 and 1 and would like to get an Integer out of it: String bitString = ""; int Number; int tmp; bitString = ""; for (i=1;i<=10;i++) { tmp= analogRead (...
0
votes
1answer
2k views

Adafruit motor shield + Adafruit stepper not working

I have the Adafruit Motor Shield V2 and an Adafruit stepper motor. I have not soldered the shield onto the Arduino (which is an Uno) yet because I don't want to make anything permanent yet. I have the ...
4
votes
1answer
2k views

How to make XBee module interrupt/wake arduino

What I am trying to do is, to have arduino in low power mode and waking up only when a packet is received and is available to be read from the buffer. A scenario : Zigbee XBee module is not ...
2
votes
3answers
4k views

Solar Tracker Code - how to limit steppers to max & min angle?

a couple of friends and i are working on a double axis solar tracker with a Adafruit Motor-shield V2 and 2x Adafruit bipolar stepper motors (200/rev). We got the following code so far but are stuck ...
1
vote
1answer
1k views

Calculating location with 4 piezo's

i've got the following problem i'd like to get solved and i'm breaking my head, so please help! I have a rectangle with the following size 40 cm * 50 cm. On each corner of this rectangle I placed a ...
4
votes
2answers
822 views

Formula / calculation of the function random() / randomSeed()

In which file can I find the calculation that is called with random()? If it is not too much could you also post the content in your answer? I am using an Arduino Uno and its standard IDE. I found ...
18
votes
1answer
48k views

Reset an Arduino Uno in code

Is it possible to reset an Arduino (i.e., to reboot it) from code (i.e from the sketch itself)? I know that is possible with a special circuit but is there a chance to make it just with code? Below ...
-1
votes
1answer
212 views

How Server request happens?

Can somebody explain the below code, like how the server understands, how the request goes to the server from the below code. if (client.connect(server, port)) { client.print("GET /abc.txt"); ...
1
vote
1answer
2k views

Setting up the MMA8452 to trigger interrupt

I am working with the MMA8452q accelerometer by Freescale. I am trying to set it up to be in low power mode, to go to sleep when no motion has happened, and to wake up due to motion being detected ...
1
vote
1answer
331 views

digital pin's current limit, ohm's law and DC motor

A digital pin's output voltage on an UNO board is 5V, which is equal to the output from the VCC. I read that the DC current limits of those pins are 40mA and 200mA respectively, and that a higher ...
0
votes
1answer
1k views

SMS in modem's memory

I am working on SMS communication with my phone and Arduino. My intension is simple. When somebody send an SMS, the Arduino should read a text file located on my server and forward the content to the ...
12
votes
4answers
22k views

What's the deal with Uno's pin 13 LED?

(I have a Sparkfun RedBoard, but this question seems to apply to R3 Unos and Uno-compatible boards.) As I was building the first circuit in my SIK guidebook (add a resistor, LED, hook it up and make ...
-2
votes
1answer
420 views

Receive SMS example gives me a garbage values

When I run my Receive SMS example code, By default every time I get the same thing.I am trying to send sms to my sim card present in the Arduino GSM shield. I don't want this message. How to solve ...
1
vote
1answer
1k views

GSM and GPS shield pin conflict

I have an Arduino GSM shield and I plan to purchase an Adafruit GPS shield. The GPS module uses Pin 7 & 8 for Rx and Tx, but the GSM shield uses Pin 7 for Modem Reset. Will the overlap on pin 7 ...
3
votes
1answer
2k views

How to read a Text file from server and store to a separate variable?

I am working on reading a text file from the server, using http://arduino.cc/en/Reference/GSMClientConnected. It gives me this code: char path[]="/asciilogo.txt" I want to store only the contents ...
5
votes
1answer
351 views

Is the Sparkfun RedBoard pre-loaded with a blink sketch?

As soon as I plugged my brand new RedBoard (Sparkfun's Uno) into my computer, I saw the onboard LED (for pin 13) blink on and off every 1 second. This was before I even sent the first demo sketch to ...
3
votes
2answers
15k views

How to receive data from my server database to a variable in my Arduino?

I am learning to work with the client - server communication. I am able to communicate with my server and able to store values in the table. But I want to receive one of the specific data from the ...
1
vote
2answers
530 views

Figuring out some numbers for a mini pump

I'm just now getting into electronics (I don't know why I waited so long) and I'm just figuring out some stuff. I picked up an Arduino kit from Vilros.com and a few other parts for my project. I'm ...
1
vote
3answers
4k views

client.connect() fails except the first time

I am communicating with the Web server's database via Arduino GSM shield + GPRS connectivity void loop() { if (client.connect(server, port)) { ....... } else { ...
4
votes
3answers
3k views

Arduino shield stacking

I have an Arduino GSM Shield mounted on an Arduino Uno. Can I stack this GPS shield above Arduino GSM shield? Will there be any pin configuration problem? In GSM Shield hardware pin’s configuraton ...
4
votes
2answers
2k views

how does serial port communication work under the hood?

im just looking for how to send/ write date to pc over serial port from arduino..vice versa. I have few Question to ask after taking so much time and couldn't figure it out myself. I hope you guys ...
0
votes
2answers
92 views

Processing Input

How to make an input from computer using processing (like a password form) and trigger pin in arduino? If you let some link to read more that would be very helpful.
1
vote
1answer
542 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
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) ...
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
514 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
310 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 ...
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 ...
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 ...
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 ...
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. ...
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
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, ...
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. ...
2
votes
1answer
1k views

ArduinoUno+LcdKeypad+ArduinoWifi=Pins Problems

Is it possible to connect these two shields to my Arduino Uno? After a research on the internet, I discovered that they use some of the same pins. Even so, is it still possible for me to connect the ...
6
votes
5answers
7k views

My Servo Won't Sweep Smoothly

So I've tried this a few times and I always get the same issue. When I try to run the sweep example the servo goes round 180 degrees but only in steps. Anyone know a way to fix this? The servo I'm ...
-2
votes
1answer
882 views

Analog average sample wind speed sensor

I have wind speed sensor that can measure max speed upto 30 m/s with analog out put 0-5v. I have simple code calling from the loop. When I put the wind speed average code, the web server is not ...
2
votes
2answers
3k views

Turning a DC motor a set number of Rotations using an encoder

I'm using an arduino UNO, and i want to turn a motor a set number of revolutions, i'm trying to read the clicks of the encoder which has a resolution of 360 clicks/ revolution, my logic is that i ...