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1500 questions
4
votes
2 answers

Locally declared variable takes up global variable space in dynamic memory/SRAM

I'm trying to make my Arduino Uno control the air conditioner by recording the raw IR signal of several of the AC remotes temperatures using AnalysisIR. However these IR codes are quite long (array with 343 items). Declaring more than one IR code…
ihish52
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4
votes
2 answers

Convert Arduino Pro Mini 5v to use 3.3v

Id like to make my 5v pro mini use 3.3 v instead of 5 because i want to use it in an existing piece of electronics that uses 3v throughout. Looking at the specs for the pro mini it says the 3.3v version can accept higher voltages. So is there a…
S Rosam
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4
votes
2 answers

Interrupts: use of the "volatile" keyword with a structure pointer for button debounce

I've written a small sketch targeted at the Arduino Uno (ATmega328P) to debounce a mechanical pushbutton using the summing/integration technique: #include #define PIN_BTN 4 IntegratingDebounce *btn; ISR (TIMER2_OVF_vect) { …
Gutenberg
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4
votes
2 answers

FastLed LED Strip Output Checksum

I am wondering if anyone has ever connected the output of their LED strip back to the Arduino to read and make sure the strip is functioning correctly, kinda like checksum functionality. I am using the FastLed library and it doesn't appear that this…
Jorb
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4
votes
1 answer

How do you convert a formatted print statement into a string variable?

I'm using the following routine to print the current time on the com port. I would like to capture this as a string so I can display it using ePaper. void printLocalTime() { time_t rawtime; struct tm timeinfo; …
Simon Markham
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4
votes
1 answer

How to listen to multiple server ports with ESP8266?

I'm using WeMos D1 R2. I'm trying to listen to both ports 1992 and 1993. This is my current code: #include WiFiServer server_1992(1992); WiFiServer server_1993(1993); void setup() { Serial.begin(9600); WiFi.begin("MySSID",…
MoonFan
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4
votes
5 answers

Arduino Yun external antenna

Can someone help me understand how the external antenna IPX connector actually stays connected to the Yun? Do I have to "force" it in so it snaps in? I've been somewhat gentle with it in fear I'll break something. However when I get close to getting…
Pat
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4
votes
1 answer

Interrupt fires a random number of multiple times for one pulse

This is my first time posting on this forum. I have tried to format this question properly, but let me know if I need to correct anything. I searched to see if someone else had a similar problem, but let me know if someone has already answered this…
4
votes
2 answers

Is there alternative to arduino IDE program ESP8266 and ESP32 with arduino toolchain?

I use ESP8266 and ESP32 with arduino toolchain rather than pure arduino hardware. Arduino IDE is standard and proven but what are the other IDE and advantage/disadvantage ?
E.Racineux
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4
votes
5 answers

What does Arduino do in 15ms?

I was wondering why there is a 15 ms delay between each iteration of a the main loop. Code: The following code shows the execution time expressed in microsec between each loop void setup() { Serial.begin(9600); } void loop() { …
UserK
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4
votes
2 answers

Why do people complain when I call my functions voids?

I have posted questions about "my void loop" or "my void setup" and people complain that they aren't really voids. But they are! See this example code: void setup() { pinMode(13, OUTPUT); } void loop() { digitalWrite(13, HIGH); // turn the…
Nick Gammon
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4
votes
1 answer

Turn off the second builtin Nodemcu 0.9 led

I'm making a low energy consumption device so I'd like to turn off all the led when I'm idle. Unfortunately the nodemcu turn on a blue led while I'm idle (during delay(ms)) Here is my code: #define LED 16 void setup() { initialSetup(); …
Timmy
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4
votes
1 answer

How to switch an external circuit with Arduino?

I have an object with a series of led and I want to turn on and off these leds from my Arduino. The input of the LED circuit is 24v DC 100mA. What I've done is the following: I've cut a wire of this object and I connected one end to the collector…
Alessandro
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4
votes
1 answer

Is there a way to disable modules like ADC without a sleep mode?

I'm working on a binary watch project. I want my circuit to live off of batteries for as long as possible, so I want to decrease the power consumption of my chip. I'm using a barebones ATmega328P-PU with two 74HC595 shift registers. The ideal…
thallia
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4
votes
1 answer

Modbus RTU controller monitoring with arduino and RS485 module

I'm a medium user in Arduino. I baught a pHmeter controller with RS485 output (MODBUS RTU protocol). I want to get pH value read by the controller over RS485 module and Arduino. According the controller's manufacturer, we should operate as…
Teddol
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