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An IC that offers Wi-Fi networking compatible with b/g/n standards. It also has integrated TCP/IP protocol stack. Extremely popular along IoT community as a low cost and powerful board.

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How can I connect my Arduino to a SQL Database with esp8266?

I'm trying to make a project using Arduino, MySQL and ESP8266 but I just got stucked with the issue that the esp8266wifi.h lib doesn't work with the Arduino board, only with the NodeMCU board. Is ...
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0answers
2 views

ESP8266 not accessing php file

I'm trying to control NodeMCU via android application and i can control NodeMCU easily but when i added the url to hit the php code to enter data in mysql neither NodeMCU is controllable nor NodeMCU ...
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2answers
13 views

Using MQTT to send time stamp - to Arduino

In previous question in this forum - I asked about updating clock on an ESP8266, using MQTT broker to send a time stamp on demand, in following manner: 1) ESP8266 sends a publish containing the ...
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0answers
18 views

Question on basics: Getting signal strength between ESP8266s as APs and Arduinos

Apologies for the potentially newbie question, but I'm quite new to the ESP8266 and wireless. My end goal is to have several Arduino-ESP8266 pairs, and to have the Arduinos able to access the signal ...
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2answers
22 views

ESP-01S Relay V1.0 connection with Arduino

I am new to Arduino Let me ask you about IOT(internet of things). I want to connect ESP-01S Relay v1.0 Where does the NC port goes on Arduino? Is it TX or RX? Also, where does the NO goes on ...
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1answer
28 views

Use MQTT to update internal clock

I write code to upload to ESP8266. I wish to use time stamp in order to log events. I found an NTP sketch, I can work with ( since it has a wifi connection ), but I wish to keep my code as simple as ...
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1answer
17 views

Arduino Uno - MQTT message using PUBSUB on ESP8266

I'm trying to write code involving MQTT messages to operate an ESP8266 relay ( a Sonoff device ), using PubSub library. For some, unknown for me, reason - messages larger than 99 chars are not sent. ...
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0answers
17 views

ESP8266 getCycleCount() Randomly Delays [on hold]

I am trying to get 6.25ns resolution timing using interrupts with an Adafruit ESP8266. In my loop() I have: t1 = getCycleCount(); t2 = getCycleCount(); where t1 and t2 are volatile int32_t variables ...
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1answer
20 views

Is it possible to send data from Arduino to ESP8266 Thing Dev and vice/versa?

I am interested in using the Sparkfun ESP8266 Thing Dev and an Arduino UNO to: Send sensory data from Arduino UNO to a database via the ESP8266 Retrieve data from a database via the ESP8266 and send ...
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1answer
17 views

Arduino sketch for NodeMCU v1.0 (ESP8266-12E) has no error of compiling but does not run on NodeMCU v1.0 (ESP8266-12E) Board

i compiled a Arduino Sketch for NodeMCU v1.0 (ESP8266-12E) which have no error while i test with verifiy button in Arduino IDE 1.8.6 but i don't know what is the problem when i upload and test it . it ...
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1answer
18 views

Connecting multiple topics- MQTT

I'm configuring an ESP8266 using Arduino Uno. I have several MQTT topics I wish it to subscribe, and I do not want to repeat code 3 or 4 times ( in Python I would have created a list - and make a for ...
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1answer
43 views

How to pass non-static class member to callback?

I am using the arduinoWebSockets library in my own Arduino library. I'm having trouble with trying to assign a class member as the websocket library onEvent callback function. MyClass.cpp: #include &...
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1answer
39 views

How to detect when intercom is ringing?

For my apartment, I need to check when intercom is ringing and call an API in that case. I was thinking about using an AC input / DC output relay, since the buzzer signal is an AC signal. Is there an ...
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1answer
30 views

How do I select Sensor using chip 74HC138 on Wemos D1 Mini?

I have a project for my graduate degree. It's about Monitoring Temperature and Humidity using Message Queuing Telemetry Transport on Serial NodeJS. To get sensor data to Wemos D1 Mini and NodeJS had ...
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0answers
5 views

How easy would it be to program this ESP8285 implementation? [migrated]

This question has more to do with the physical pcb than it does Arduino. If you know where I should be posting this question, please comment and I will move. I figured I would find like-minded people ...
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2answers
74 views

1-10 volt analog signal

I have an Arduino project where I am using an ESP8266 (Wemos D1 mini) powered via USB. I want/need to output an analog voltage from 0 to 10V. Goal: A solution that is pre-made (eg a shield or ...
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4answers
64 views

for() loop doesn't seem to break?

So I'm quite new to the whole Arduino coding but constructed a sketch that does work, but I think it doesn't work properly. So I'd love to get some advice on how to improve it. This script is ...
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1answer
33 views

Cannot run WiFi sketch on ESP-01

I can upload simple sketch on my ESP-01 like: void setup() { Serial.begin(115200); Serial.println("Hello there"); } void loop() { Serial.println("Hello from loop"); delay(1000); } I also ...
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1answer
27 views

How to avoid electromagnetic interference on ESP32 input

I've realized a simple circuit like the following, in order to implement a rain gauge that I can access via HTTP: With the following sketch: #include <WebServer.h> #include <WiFi.h> #...
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2answers
54 views

shift register 74HC595 enable specific pin

Its driving me crazy for some couple of days now and i don't get the answer. I'm busy to setup a irrigation system with a shift register 74HC595 and a 8 channel relay board. I see a lot of sketches ...
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1answer
40 views

Wemos D1 EEProm put/get not getting correct value

Hey all I have the following code in my Arduino IDE: #include <EEPROM.h> #include <ArduinoJson.h> bool debuggin = true; int brightness = 255; int ambientLight = 30; ...
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1answer
25 views

Error running FirebaseDemo on nodeMCU

So I followed the guide on GitHub to run this demo which compiles and runs. It does warn of some deprecations and such in the firebase libraries : In member function 'const String& ...
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0answers
25 views

ESP8266 stops working after 5 requests

I am trying to implement a TCP server on an ESP8266. My code looks like this: void http_recvcb(void *arg, char *data, unsigned short int length) { Serial.println("Received data"); ...
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1answer
12 views

Adafruit Huzzah ESP8266 Battery Power issue

I'm trying to connect a ~5.5V (2 x 3V coin cells in series, but their voltage drops a little) to the VBat (or V+) of my Adafruit Huzzah ESP8266 module (not the black Feather one, the smaller blue one: ...
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1answer
34 views

Can a DHT11+ESP8266 be powered by a Adafruit USB LiPo charger directly?

I have rigged up a small DHT11+ESP8266 combo which I'm currently powering from the 3.3v from an Ardruino. I've ordered a 3.7v LiPo battery and have a Adafruit usb micro LiPo charger, however, the ...
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1answer
39 views

Is there any easy way to change Arduino Wifi shield to ESP8266?

My old question was put on hold. Probably wasn't too clear, sorry. As the title says, is there any easy way to replace Wifi shield with ESP8266, with as little as possible modification to code? ...
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1answer
54 views

The right way to find and understand the libraries

I am working on a project to send sensor values from esp8266's Wemos D1 mini to MySQL. I tried using the library MySQLconnection.h but I couldn't make it to connect to wifi. So I uploaded a simple ...
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0answers
53 views

ESP32 : Disable Brownout Detector

I have an ESP-WROOM-32 and I'm using Arduino IDE to push code on it. My ESP is powered via 2 AA battery and got one power supply problem. It works well on new battery but after a bit, I will always ...
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1answer
38 views

ESP8266 fail to connect MQTT broker

I am using NodeMCU dev board with ESP8266 WIFI. Every time I try to connect to my local broker it returns this error: failed, rc=-2 try again in 5 seconds I am using Ubuntu 18.04, my local brokers ...
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1answer
57 views

Keep on getting scandone

I have a node server with express and socket io behind nginx reverse proxy at AWS. I am try to connect remotely from my NodeMCU esp8266 through websocket io client to my server using ...
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1answer
71 views

Secure HTTPS request fails 90% of the time

I'm using a NodeMCU, which is connected to an enterprise network at a school. The information given in the GET requests that the ESP8266 sends is sensitive, so naturally we want to make it secure and ...
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1answer
73 views

ESP8266 - does it really have terrible wifi range by default?

ESP8266 - does it really have terrible WiFi range by default?? First time to try this module out and we're disappointed with the range.. as per our testing we can only get max 5m WiFi range line of ...
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1answer
26 views

NodeMCU 12E V2 Power Saving

I'm powering a NodeMCU with 4 x AA batteries (6v, ~9,600mAh). I am running ESP.deepSleep([milliseconds]) to minimize power consumption. Even with deepSleep I am seeing a precipitous drop off in ...
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1answer
35 views

ESP8266 12-E can't connect to any Access Point with converted variables from strings to char arrays

I'm using an esp8266 12-E nodemcu I wrote a code that scans the available WiFi networks, print them through serial communication,ask the user which network he wants to connect to and then the password ...
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1answer
36 views

Memory leakage caused by String Concatenation

In this link, section "Memory, memory, memory" it's been told that doing many String concatenations in sequence, e.g.: using operator+() multiple times, will cause memory fragmentation, which may lead ...
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0answers
27 views

Arduino send water flow value to thingspeak

I am new in arduino coding. Currently I am trying to upload water flow value to thingspeak via esp8266. It can connect to the wifi but can't send the value to thingspeak. Please help me in this. ...
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0answers
58 views

Communication between 2 ESP8266 devices using Arduino code

Perhaps it is a novice question (since I'm a Pythonist, and I'm new to Arduino), but I'm trying to implement my code in Arduino to test if it is more stable than MicroPython. I have an AC motor, that ...
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2answers
50 views

How should you predict the battery size required for a project?

I am using an Arduino nano along with an ESP8266. The nano is connected to an OLED display and a keypad. The ESP8266 uploads the data entered from the keypad onto a server. I wish to make the device ...
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1answer
23 views

esp8266 and arduino pro mini [closed]

I have few sensors. Temperature sensor (DHT22), flow rate sensor, rpm optical tachometer sensor and a rgb led. I want to use adafruit IO to get values of these sensors and change the colour of the ...
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1answer
21 views

Problem with html code in ESP8266 WebServer

Here I have a small problem: I have an ESP8266, to which I have connected a matrix of LEDs to move text (the array of LEDs is made with the tape of LEDs addressable ws2812); when you turn on the ...
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1answer
23 views

sending and recieving data from esp8266

We're trying to make an network of connected cars in which the status of one car is continuously updated to the nearby cars (for example, speed, gear, brakes, etc.). Can I continuously send out ...
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6answers
112 views

How to parse 20180810T143000Z to time_t

What is the shortest/most elegant way (i.e. use existing lib functions) to parse a string in the form of 20180810T143000Z to a time_t? Note that the literal always represents a UTC timestamp. I ...
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2answers
97 views

NodeMCU - use flash button as input in loop()

I couldn't find a proper answer on the net so I came here as a last resort. So I want to use the FLASH button as an input in the loop() method. Is there a way the check if it's pressed or not?
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0answers
39 views

JSON woes: parsing JSON with esp8266, can this be more elegant?

A few years back I wrote a program that pulled bus time data from the NYC MTA's "bus time" API and posted it on a wifi-connected OLED on my wall. All was well for a few years, but they changed the ...
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2answers
33 views

How do I read addresses on multiple DS2413 1-Wire GPIO Breakouts, using the Adafruit sketch?

I am using three DS2413 1-Wire GPIO Breakouts from Adafruit connected to an ESP8266. I tested the DS2413 breakouts using their example sketch and it works fine for just one DS2413. But I cannot ...
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1answer
19 views

Arduino sketch- How to add Time Stamp for outgoing MQTT

I'm writing a sketch in order to upload to a Sonoff device ( Remote relay, based ESP8266 ). All is working great, but I wish my MQTT pubs to contain following format: [ DATE & TIME ] msg ...
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1answer
61 views

Problem with serial connection. Data garbled

I have a hardware device that sends data over the serial port and over a socket connection. I have the TX of the device connected to the RX of the ESP8266, RX of the device to TX of the ESP8266. ...
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1answer
38 views

ESP8266 timer to trigger actions (logic issue)

so I have an application in which there are 2 specific times (eg 9AM, 6PM) where a variable curPos is updated. Everything is converted in ms since 00:00 (9AM = 32400000, 6PM = 64800000). Now, the ...
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2answers
44 views

ESP8266HTTPClient conflict with other libraries?

I can successfully send a GET request with the ESP8266HTTPClient library in the first sketch. However the exactly same code won't work when used in the second sketch, which is more complex and uses ...
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0answers
23 views

HID card reader with NodeMCU ESP8266 reads all zeroes

I have connected an RFID HID PROXY PLUS card reader with a NodeMCU ESP8266. It will read the card and send the data to database. It was working fine, until this evening. But for testing purpose I ...