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For questions about NodeMCU, an open source IoT platform which includes firmware for running on the ESP8266.

2
votes
2answers
40 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?
0
votes
1answer
29 views

Problems with NodeMCU and Relay

I've connected the MCU to a cheap chinese 24/12v to 5v car phone charger and hooked some wires to a relay.When I try to program doesn't matter if the pin is set to high or low , as soon as I touch the ...
0
votes
0answers
18 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 ...
0
votes
0answers
25 views

How to Connect multiple NodeMCU in daisy chain configuration [closed]

I am working on a project that requires multiple NodeMCU's connected to each other in the Daisy Chain configuration through WiFi. For example, if I have 3 NodeMCU's (say A, B and C). A should send ...
0
votes
0answers
14 views

Upload sketch to ESP8266 - both old and new sketch working in parallel [duplicate]

I am getting to know the ESP8266 by using a NodeMCU programming board. To upload sketches I use the Arduino IDE. Until now I have not done any programming myself, but simply tried the sketches that ...
0
votes
1answer
32 views

YL-38 output to NodeMCU v1.0 analog input

Using a YL-38 and NodeMCU v1.0 I am trying to achieve what the first link is doing, take a soil moisture reading. I've done this on an arduino, but the conversion from an arduino nano to a nodemcu is ...
0
votes
1answer
29 views

How to use RTC memory in NodeMCU to count awakes from deep sleep?

Problem: I need to retry at least 3 times (before giving up) to reconnect my NodeMCU if it doesn't get connected to Wifi, through deep sleep cycles in order to save batteries. I thought to use RTC ...
0
votes
0answers
18 views

Connect NodeMCU to serial print “live”

My NodeMCU device is working on its own batteries. Form time to time I need to connect it to the computer and use the serial print monitor, but I have no display even after a reset. To see the monitor ...
0
votes
0answers
21 views

How to debug NodeMCU?

my NodeMCU v.1.0 is running each 30 minutes. It gathers several data, uploads them on a server, and then it goes into DeepSleep for 30 minutes. I have deeply tested this process while connected with ...
0
votes
1answer
33 views

Reading file from SPIFFS in nodemcu using ArduinoJson

#include <ArduinoJson.h> #include <FS.h> /* Set these to desired credentials in runtime */ struct Config { String ssid = ""; String pass = ""; bool hFlag = false; }; void ...
0
votes
1answer
49 views

NodeMCU v1.0 high power consumption in deepsleep

I am using a NodeMCU v.1.0 ESP-12 for a small project. It is powered by 3xAA batteries (4.5v) in Vin, but to reduce power consumption I need to put in in deepsleep every now and then. Running this ...
0
votes
1answer
30 views

Help in “An error occurred while uploading the sketch”

Trying to test THIS. Got following error: esptool v0.4.13 - (c) 2014 Ch. Klippel <ck@atelier-klippel.de> setting board to nodemcu setting baudrate from 115200 to 9600 setting port ...
3
votes
1answer
114 views

Difference between these two NodeMCU boards?

I recently received a NodeMCU (identical to the one shown in the first picture below) and originally, I was unable to connect it to my computer which eventually turned out to be driver issues; however,...
3
votes
1answer
75 views

Correct way of having loop end when required?

I'm brand new to Arduinos. I'm currently trying to modify a script from here which at the moment, simply turns an LED on or off depending on which HTTP GET request it receives. However, I want to ...
0
votes
1answer
39 views

NodeMCU capable of key injection?

Short version: Is the NodeMCU capable of key injection in the same way that an Arduino Teensy can be programmed with Duckuino script to function as a HID? Long version: Recently, my 7+ year old iMac ...
1
vote
1answer
46 views

Flashing NodeMCU with .ino file?

I'm brand new to the Arduino world. I recently purchased a NodeMCU in order to have it act as a sort of foothold to get into Arduinos as it's something I've always wanted to do. However, it was only ...
0
votes
1answer
60 views

NodeMCU V3 + SD Card with Arduino IDE Not working

I am trying to connect CATALEX MicroSD Card adaptor to new NodeMCU V3 and PIN configuration are as below, NodeMCU ---------> SD Card GPIO13 (D7) ------> MOSI GPIO12 (D6) ------> MISO GPIO14 ...
0
votes
2answers
46 views

5v relay module

I'm using NodeMCU with 5v relay module. my problem is that when the output of NodeMCU is high the relay is off. Which means that the relay module work in an inverted way so how can I treat this issue ...
0
votes
0answers
8 views

Node Mcu DHT11 Update set temprature

I am using Node mcu with DHT11 . I could able to display temperature & humidity on local web server.I want parameter set temp it can be changed from local web sever. Now i could able to create ...
2
votes
2answers
61 views

Setting pinMode(pin,input/output) as per user requirement

I am working on arduino IDE and esp8266 nodemcu. As i am going through the IDE I saw that there is a structure of void loop() and void setup() and all examples in the internet included defining the ...
0
votes
1answer
23 views

Fade effect analog RGB strip and NodeMCU

I have an analog or dumb RGB strip that I control with HTTP commands. I want to be able to make the strip fade between different colours when I call http://XX.X.X.XXX/fade. I want it to do this ...
0
votes
1answer
250 views

NodeMCU (Arduino IDE) 'DynamicJsonBuffer' was not declared in this scope

#include <Arduino.h> #include <ESP8266WiFi.h> #include <ESP8266WiFiMulti.h> #include <ArduinoJson.h> #include <ESP8266HTTPClient.h> #define USE_SERIAL Serial ...
0
votes
2answers
38 views

How can I power a servo and Arduino from the same power supply?

I have an ESP8266 NodeMCU which I'm using for an automatic blinds project. The NodeMCU struggles to power the servo on its own, so at the moment I am using a 5 V supply for the servo and a USB ...
0
votes
0answers
30 views

ESP8266 consistent high ping vs NodeMCU very low ping

I bought a NodeMCU and two normal ESP8266 modules. I flashed new firmware from the official website for the modules and it worked fine. However, the ESP8266 module consistently goes over 300+ ms ping ...
0
votes
0answers
31 views

Arduino loses communication with bluetooth when sending commands to nodemcu esp8266

i've been working on a project using an Arduino UNO, Bluetooth Module HC-06 and NodeMCU esp8266, the project consists on turning leds on via bluetooth and telling the esp8266 that the leds were turned ...
0
votes
2answers
164 views

To send data perpetually from multiple clients to a server using NodeMCU?

I am working on sending data from multiple clients to a server, all of which are NodeMCUs. I have been able to send data for a single iteration. Trouble arises when I want it to send data repeatedly ...
0
votes
1answer
27 views

Sending multiple messages over the serial monitor in nodeMCU

I am trying to send multiple messages wirelessly from one ESP8266-12E NodeMCU to another. I have successfully established the connection and am able to send and receive single messages. The MAC ...
0
votes
1answer
37 views

Problem with nodemcu esp-01 can't connect to wifi

i've been working on a project that im using an esp8266 nodemcu-01 as described in the title, and i've been having some headache with this module, first because after searching i figured out that the ...
0
votes
2answers
38 views

Run Time Error in arduino

I am trying to communicate multiple clients to a server, all using nodeMCUs. I am getting a weird run time error at the Server Serial Monitor of Arduino IDE when I upload the code. Here's my server ...
0
votes
1answer
47 views

Waterlevel sensor disrupts PH reading

I have a water level sensor and a PH sensor connected to my nodemcu via an ADS1115 . When I insert only the PH sensor into the water then everything works fine. But when I insert the waterlevel sensor ...
0
votes
0answers
40 views

WiFiClientSecure client.connect(ipv4, port) always failed on connect function

Hardware: Board: (ESP8266 NodeMCU V2) /Core Installation/update date: (2018/03/21) /IDE name: (Arduino IDE) /Flash Frequency: (...
1
vote
1answer
69 views

Powering a water pump with nodemcu [closed]

I want to use a nodemcu to water my plants. I connected a pump with a 2N2222 transistor (I know i should add a diode and a pull down on the gate). The pump is DSL370 and when it is off i measure 4.4V ...
0
votes
0answers
35 views

arduino connected with ultrasonic sensor(HC-SR04) and weight machine

I am interfacing weight scale and ultrasonic sensor with Nodemcu. -heightsensor Trig Pin is connected with D8(15) of nodemcu -heightsensor Eco Pin is connected with D7(13) of nodemcu -weight machine ...
0
votes
3answers
97 views

post data from node mcu to my sql database

#include <ESP8266WiFi.h> const char* ssid = "xxxx"; const char* password = "xxxxxxxxxx"; const char* host = "192.168.43.18"; const int ldr = A0; int val = 0; void setup() { Serial.begin(...
0
votes
0answers
191 views

Controlling motor direction with ESP8266 and Motor Shield

I recently acquired a NodeMCU ESP8266 Board and a NodeMCU Motor Shield, which I have connected very simply to two motors on an RC car. The idea mostly came from this tutorial. From what I understand ...
0
votes
0answers
22 views

DC Motor Not Braking

I have a brushed motor hooked up to a NodeMCU that moves a plate left (moveLeft) and right (moveRight). When a button (buttonOpen) is pressed, it turns to the left until the plate hits a limit switch (...
0
votes
1answer
181 views

Read both battery voltage and analog sensor value with NodeMCU ESP8266

I have a soil sensor that reports value once every 5 minutes, deepsleep in between. Is there a way to also report battery voltage (with ESP.getVcc())? To get the battery voltage reading to work I ...
-2
votes
1answer
252 views

Connect NodeMCU with USB Camera

I am trying to connect a USB Camera with my NodeMCU v0.9. VCC Red +5V D- White Data D+ Green Data GND Black Ground I dismantled the USB-...
0
votes
0answers
38 views

Controlling motors via accelerometer not working

I want to control the 2 servos(pan tilt) using accelerometer data value from android app. Im using nodeMCU v3, 2 servos(pan tilt) and smartphone. Connection: servos(pan tilt) is connected to 5 v ...
0
votes
0answers
146 views

Trying to use NodeMCU ESP-12e, a 5v relay AND a solenoid lock on same 12v power wall-wart

Noob here, so be gentle. Using a 12v-5/3.3v power board, NodeMCU powers relay fine, 100% of the time. Add in the solenoid by soldering a line from the wall wart into the COM spot on the relay, and ...
0
votes
1answer
73 views

Will Nodemcu support 4AAA

Will Nodemcu support 4AAA batteries which is 6v approx, or should i go with 3AAA batteries which is 4.5V approx. And one more question , is it ok to use AA instead of AAA ?
0
votes
0answers
17 views

MacOS cannot find NodeMCU device [duplicate]

I'm trying to mount a NodeMCU device to my mac to upload an Arduino sketch to it. I can verify that I am using a micro USB data cable, but mac doesn't recognise that a device has been plugged in. ...
0
votes
0answers
64 views

Getting error with my Nodemcu

I have been trying to upload a simpley software code to my nodemcu arduino, but i keep getting this error : exec: "C:\Users\jean-claude\AppData\Local\Arduino15\packages\esp8266\tools\xtensa-lx106-elf-...
0
votes
1answer
48 views

Interesting issue with my wifi Car project

Hello so i build a nodemcu wifi controlled car, everything works fine expect i have one small issue, currently i have 2 9v batterys, one of them is connected to motor controller and other one is ...
0
votes
0answers
32 views

GPS is working but Distance is always showing 0. Can't calculate Distance in this code

#include <TinyGPS++.h> #include <SoftwareSerial.h> #include <ESP8266WiFi.h> #include <WiFiClient.h> #include <ESP8266HTTPClient.h> #include <ESP8266WebServer.h> ...
0
votes
0answers
102 views

Soft WDT with HX711 and PubSubClient libraries

I'm using NodeMCU 0.9 My sketch crashes if the following 2 include are present in the sketch: #include <PubSubClient.h> #include <HX711.h> I obtain a Soft WDT reset If I do not use ...
0
votes
1answer
20 views

nodemcu pins + sensors reading values

what are the SDA & SCL pins in NodeMCU? (Pins 20 & 21 in Arduino MEGA2560) I already implemented a simple project to read 2 accelerometers values from Arduino and send them through wifi to ...
1
vote
1answer
23 views

NodeMCU ESP12 Voltage

I'd like to power an NodeMCU off of four 1.5v batteries. That's 6v. Depending on the source I've read that 5.1v will fry the board and, just a few clicks later, that the board will take up to a 20v ...
1
vote
1answer
155 views

Connecting LCD TFT shield to NodeMCU

I have the following screen: I want to connect it to a NodeMCU device: I read somewhere that it is not possible. However, I am not interested in the touch ability nor the SD card. I just want to ...
1
vote
1answer
220 views

ESP.deepSleep() - over and over?

Important note: the esp.deepsleep function uses microseconds, not milliseconds. I posted another question here asking for clarification on how an RTC can be used to put a NodeMCU 12 to sleep for a ...