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1500 questions
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5 answers

My DS18B20 is reading high. How can I get it to return the correct temperature?

I am working on a heating control system for my home, but having problems with the temperature sensor reading higher than I expect. I have a 5V Arduino Mini Pro clone hooked up to a relay module, an HD47780 display and a Tiny RTC module, with a…
Mark Booth
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3 answers

What alternatives are there to the Optiboot bootloader?

Nearly all modern Arduino boards use the Optiboot bootloader. Compared to the ATmegaboot used before, this is smaller in flash terms (by about 1.5KB) and faster in upload speed (115.2k vs 57.6k) and starts your sketch quicker (the delay whilst…
Cybergibbons
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6 answers

Addressable RGB strip works fine individually but cannot set all LEDs to full white

I have a 5 meter strip of 12V digital RGB LEDs. The chip is WS2811 (see photo of IC). There are 50 addresses on the strip. Using the FastLED library, I am able to run the "FirstLight" example that chases full white with a single address at a time,…
Bort
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4 answers

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 to upload the hill data to the server via Wi-Fi. I…
R Harrington
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13
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1 answer

Arduino Nano ATmega328P bootloader difference

There are two ATmega328P bootloaders, old and current. What is the difference between these bootloaders? I'm aware that Nanos sold by Arduino use the new bootloaders but I haven't been able to find any release notes about the bootloader.
Claus
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13
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4 answers

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 not random enough. If possible the method should…
Rexcirus
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13
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4 answers

How to show the º character in a LCD?

I have a 16x2 LCD and I want to show a temperature: 23 ºC. But the º symbol is not properly shown. It shows a strange character instead of the º symbol .
Roby Sottini
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13
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4 answers

Is setup and loop provided for convenience?

Arduino sketches usually feature a setup and loop function. Are these functions only provided for convenience or do they actually have special purposes? (e.g.: are some operations disallowed or allowed in setup and loop) Are these two pieces of code…
Sebazzz
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2 answers

How to manage dependencies?

I want to include a dependency like Logging. On its page it says: Download zip file Put the Logging folder in "libraries\". I don't want to believe (with a Maven mindset) that this is the way we manage dependencies in Arduino projects. That means,…
Markus Malkusch
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13
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4 answers

Does ADC conversion to a voltage rely on the actual value of the +5 V pin?

Questions: Does the conversion of the ADC count to voltage depend on the actual voltage of the +5 V pin? If yes, what is the accepted method of getting that voltage from the board? Background/Detail: I have a circuit in which I have an Arduino…
Caribou
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13
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7 answers

Where can I find a central repository of all available Arduino libraries?

Currently; when I start a new Arduino project with some new hardware, the first thing I do is to look for 3rd-party libraries that bring Arduino support for this hardware. The first places I look are: The Arduino Playground GitHub Google Generally…
jfpoilpret
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13
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6 answers

How to output a true analog voltage at output pin

Regarding my program, it is a program that does some calculations and then outputs a voltage based on the result using analogWrite function. However my problem is that I had done my programming based on a misconception that analogWrite function via…
bytk
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13
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5 answers

How to retrieve the data type of a variable?

I am using Arduino and I would like to know if there is a function that returns the data type of a variable. That is, I would like to run something as like the following: // Note: 'typeof' is a sample function that should return the data…
user502052
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2 answers

WiFi Password Safety

Are there any best practices regarding password safety? The following is taken from a wifi tutorial sketch. #include #include char ssid[] = "yourNetwork"; // your network SSID (name) char pass[] = "secretPassword"; //…
Skiddles
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13
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3 answers

Want to create bluetooth audio control (volume up/down, play, pause, etc.) for smartphone

I want to create a bluetooth remote audio control to control smartphone audio, essentially identical in function to this type of…
Howiecamp
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