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1500 questions
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1 answer

Turning all LEDs on (FAST.LED)

In Fast.Led lib for arduino there is a code to turn off all leds FastLED.clear (); Is there also a shortcut to turn all LEDs ON, and with a specific color
Niles
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3 answers

Sending colours to vga monitor

I'm looking for a simple way to send a signal from my arduino to a vga monitor. What would be the easiest method, and what components would be needed? I don't need to display an image, just a solid colour.
Terry
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Why is there a clock in my arduino?

Of course I know it is usefull to control the time of a delay, but any other use? With a 16Mhz clock, each line of my program will take 1/16000000 second, right? even a very very big line will only take 1/16000000 of a second ? With a 8MHz clock,…
n0tis
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3 answers

Programming many Arduinos simultaneously with a wireless broadcast

I will have many microcontroller-based devices which will be independent from each other, but all will run the same program. I would like to upload a program to all of them at the same time with a wireless broadcast. Ideally the user would plug in…
MGA
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3 answers

ESP8266 Analog read interferes with wifi?

Short version: I have a program that connects my ESP8266 to WIFI so I can control a relay connected to it over the internet or a button. I also have a sensor for my door. This software works perfectly, if I add a light dependent resistor to it…
JanG
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2 answers

Re-use smartphone/tablets parts like a camera

For learning and hacking purposes, I plan to study and use parts from smartphones and tablets like Galaxy or iPhone. They are really efficient and pretty cheap... Did anybody do this before? If yes, can anybody tell me what kind of connector is this…
Charaf
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9
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7 answers

ERROR: Timed out waiting for Arduino 101 - anything I can do?

I just received an Arduino 101 so I did the following in a wave of excitement... Connected the USB cable between it and my Macbook Pro Started the Arduino IDE version 1.6.7 Wrote a little bit of code Selected Tools | Boards | Boards Manager... and…
kmp
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1 answer

Is volatile needed when variable is accessed from > 1 ISRs, but not shared outside ISRs?

It's clearly documented that when global data is shared with an ISR and the main program, the data needs to be declared volatile in order to guarantee memory visibility (and that only suffices for 1-byte data; anything bigger needs special…
Joonas Pulakka
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9
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2 answers

Arduino ADC Reference Voltage if it is Battery Powered

I am looking to possibly monitor battery power to the Arduino using its ADC. This is fairly straight forward and simple (especially if using the Arduino API); however, if the battery is powering the Arduino and is unregulated externally, won't the…
ryeager
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Does millis() conflict with the PWM pins associated with timer 0?

I've read that the millis() function uses the same timer as a couple of PWM pins. If you're using those PWM pins, will millis() still return the correct value?
Aurast
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9
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5 answers

Reasons why it is not OK to connect a relay directly from an Arduino digital pin

After looking into various schematics on controlling a relay via an Arduino, I have noticed that, most of the time, transistors are used to switch the separate supply into the relay coil rather than directly supplying the relay with the 5-Volt…
DorkOrc
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9
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2 answers

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 LED, arduino (connected at pin 9 and ground) and a…
Neuron
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2 answers

Allocate object memory statically; intialize it dynamically?

I have an object whose constructor gets passed a parameter. If I know the parameter value at compile time, I can construct the object statically: static FOOOBJ foo(3); (I understand that it isn't really done statically, i.e. by the compiler, but is…
JRobert
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3 answers

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 there anything else to do in order for my sketch…
Alex Shroyer
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9
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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) functionality on pins 9 and 10, whether or not…
user1265
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