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1500 questions
9
votes
3 answers
How to measure total energy usage of an arduino board
I have a project that I'm currently working on. We have built a green wall, wich consists of plants on a wall
Now, we have a pump situated at the bottom that waters all the plants. There is an arduino board that decides when to put the pump on.…
DLJ
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9
votes
2 answers
How frequently do you need to poll UI buttons before they are perceived as laggy?
Whilst it is possible, and sometimes desirable, to use pin change interrupts to read the state of buttons, it is simpler to poll the state of buttons in loop(). This is a commonly used technique.
If you loop() executes quickly enough, then button…
Cybergibbons
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9
votes
1 answer
Can you query the current serial port's speed?
Is there some code I can use to find out what the a chosen serial port's speed is running at ?
Hayden Thring
- 308
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9
votes
2 answers
What's the smallest (cheap) USB Host solution for Arduino?
I'm building a project that will connect to users' phones (Android at first, but iPhone too, if there's enough interest) via USB. Of course, this means that I need a USB host in the project. The total size of the device has to be about the size of…
Sniggerfardimungus
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9
votes
2 answers
Arduino interruption (on pin change)
I use the interrupt function to fill an array with values received from digitalRead().
void setup() {
Serial.begin(115200);
attachInterrupt(0, test_func, CHANGE);
}
void test_func() {
if (digitalRead(pin) == HIGH) {
…
user277820
- 91
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9
votes
2 answers
Reading a varying voltage into Arduino
Using an Arduino Nano and a current transformer (CT), I'm trying to sense the current flowing through a 120 V 60 Hz line.
Circuit
CT outputs 0-1 V according to its specifications. This output is biased AREF/2 = 2.5 V.
analogRead Values
The…
Nyxynyx
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9
votes
1 answer
Which C++ standard does the Arduino language support?
The "Arduino language" (as they call it) of the Arduino IDE 1 is obviously C++. Which C++ exactly?
I tried to figure it out myself (Arduino IDE 1.8.13 for Arduino Uno), but I can't conclude what C++ standard it supports.
From these tests, it seems…
Thomas Weller
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9
votes
5 answers
Same structure taking different memory space on Uno and NodeMCU ESP8266, leading to data corruption when transferring via nRF24L01+
I'm trying to transfer data between a Arduino Uno board to a NodeMCU ESP8266 board, using nRF24L01+ transceivers module and RF24 library on both side. The data I'm transferring are stored in a struct defined this way:
// Struct declared in both…
Vincent
- 232
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- 10
9
votes
3 answers
Bootup on lower power not functioning
I have a custom Arduino ATMega328 board that generally runs at 5V @ 8MHz (using the Arduino Pro 3.3V 8MHz profile and bootloader). The main reason I'm using this setup is so that I can put the board to sleep when main power is disconnected and it…
Adam Haile
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9
votes
2 answers
What is difference between NodeMCU and esp8266?
Since I have no previous experience in electronics I'm getting quite confused while coming across these two terms ..I'd like to know whether they're the same or different.
User 1426833
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9
votes
3 answers
I2C LCD Serial Interface Board not displaying text (wrong pins?)
I have a 1602 LCD screen that works fine on its own. However I wanted to free some pins by using an I2C / IIC LCD controller I purchased separately.
While the controller seems to be communicating with my Arduino UNO on the right address, I cannot…
Bort
- 397
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9
votes
2 answers
How can I sense very high temperatures with Arduino?
I've seen many temperature sensors, but the highest temperature they go up to is 125 degrees C (257 degrees F). I want to reach higher temperatures than that. I'm thinking about rigging up a closed loop sensor for my soldering iron (for a convenient…
Anonymous Penguin
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9
votes
3 answers
Grove sensors without a Grove shield
There exists a large variety of sensors in the Grove System. Usually these are accessed via a special shield (Grove base shield).
Can I access these sensor directly without a shield. In particular I am interested in using them with an Arduino Pro…
A.Schulz
- 467
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9
votes
3 answers
How to turn off or stop Access Point network in ESP8266?
I've created a code for ESP8266 12E with Arduino IDE, in which it'll operate as "Station Mode" or "Access Point Mode" on Wifi, depending on the situation. Everything works fine except when device was configured as Access Point, even when I turn off…
wBB
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9
votes
2 answers
How to update a variable in an ISR using Timers
I'm trying to check the frequency of Timer3 using a counter. The value of the counter, declared as volatile, is incremented in the ISR and every second the sum is shown in the main loop and the value reset to zero.
The timer has been set up…
UserK
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