We’re rewarding the question askers & reputations are being recalculated! Read more.

Questions tagged [nodemcu]

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

135 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
3
votes
1answer
3k views

Uni-directional communication between NodeMCU and Arduino spits out garbage

I am sending data from ESP8266 (NodeMCU) to Arduino using serial and 9600 baud rate on both sides. Since it is uni-directional and from NodeMCU to Arduino, I am not using a voltage regulator and I ...
2
votes
0answers
126 views

Cannot POST to server. HTTP code -1. NodeMCU

I am trying to make a POST request with NodeMCU, but I get a HTTP status code -1. Code: #include <ESP8266HTTPClient.h> #include <ESP8266WiFi.h> #ifndef STASSID #define STASSID "Wifi" #...
2
votes
1answer
834 views

Use external power - nodemcu 0.9

I'd like to deploy my project so I'm looking for a way to power the nodemcu. I'd like to know if there's a way to power it with a 9V battery without any other external circuit. Until now I've found ...
2
votes
0answers
8k views

UART from Arduino to NodeMCU

I'm trying to connect an Arduino nano to a NodeMCU 1.0 via the hardware UART, in order to send information one way from the Arduino to the NodeMCU (and from there to the network). I'm connecting the ...
1
vote
0answers
129 views

error compiling for board node MCU 1.0

Arduino: 1.8.9 (Windows 10), Board: "NodeMCU 1.0 (ESP-12E Module), 80 MHz, Serial, 115200, 4M (3M SPIFFS)" In file included from C:\Users\Priyaranjan Tiwari\Documents\Arduino\007mcu_php\007mcu_php....
1
vote
0answers
49 views

Serial Communication between arduino and nodeMCU

I am trying to connect a nodeMCU to arduino mega using serial communication so that i can read data from firebase. I have put the following code on the NODEMCU. #include<SoftwareSerial.h> //...
1
vote
0answers
39 views

Can't get fastled.h and remoteme.h to work together

I'm trying to make a Google Assistant controlled LED strip, but I'm stuck. I can control the on board LED of the nodemcu with Google Assistant, and I can control a LED strip too, but I can't combine ...
1
vote
0answers
91 views

Arduino IDE - debugging Exception 29

I installed the ESP EXCEPTION DECODER along with my Arduino IDE. When my sketch crashes with Exception 29, I take the stack trace and input it, but I can't understand its line references (they dont ...
1
vote
0answers
51 views

NodeMCU can't communicate with BM019 NFC via SPI

When I upload this code to UNO it works well but when I use this code with NodeMCU it does not show anything on the serial monitor. I don't have much knowledge to rectify this problem so please help. ...
1
vote
0answers
992 views

Connecting to Alexa with FAUXMOESP library not detecting the device

I am using NodeMCU (ESP8266 12E) module from some days. I am trying to connect to Alexa for voice controlling. I have Amazon Alexa Echo 2 from which I am trying to discover my nodemcu as a smart home ...
1
vote
0answers
81 views

Storing an array of objects

I followed the instructions of this post: Storing an array of function pointers. To show my problem I shorted my code extremely but the problem is still there. My classes are defined as followes: ...
1
vote
0answers
99 views

Correct wiring?

I'm doing some Home automation and am currently trying to automate my intercom system. My overall aim is to be able to detect when someone has pressed the buzzer and then to be able to open the door ...
1
vote
0answers
3k views

How to flash pre-compiled bin files into NodeMCU using Ardunio IDE

How to flash pre-compiled binary into NodeMCU using Ardunio IDE. Since every time it require to compile and flash it. Is there way to flash binary alone to nodeMCU via Arduino IDE ? One can export ...
1
vote
0answers
2k views

Digital Vibration sensor on NodeMCU ESP8266

First Post. I'm using a NodeMCU esp8266 connected to a digital vibration sensor. My project is to detect when a pager vibrates to then trigger through the maker channel of ifttt an outcome. I'm ...
1
vote
0answers
2k views

NodeMCU stops responding after several hours

I'm controlling some devices through a relay and a NodeMCU, it works fine and reconnects without problem in the meantime I'm testing it, but after I leave it like for 3 or more hours, it stops ...
1
vote
0answers
400 views

Serial Monitor Stops Working

I am using a DIY colour sensor (RGB LED and LDR) and a servo to make a skittles sorter. I am testing out just the colour detection now and printing the RGB values to serial. It worked fine until I ...
1
vote
0answers
419 views

Send .wav file from SD card to NodeMCU via serial port

I was able to send a text file in the SD card to NodeMCU using the serial port of an Arduino Mega using this code: if (readSerial1 == "Okay I'm ready") { myFile = sdf.open("uid.txt", FILE_READ); ...
1
vote
0answers
2k views

How to define SoftwareSerial pins on ESP8266

I'am new to arduino yun and ESP. In fact, i have an arduino yun which has a sim808 dfrobot shield on it which uploads GPS data online at a regular time interval. I want to connect the dfrobot sim808 ...
1
vote
0answers
331 views

Rotary Encoder on LoLin NodeMcu increases value when rotating right/left

I have a test program running on my LoLin NodeMcu board, with a Rotary Encoder connected. I use Task.h and RotaryEncoderTask.h from this library: https://github.com/Makuna/Task (though my issue is ...
1
vote
0answers
317 views

Program nodeMCU Over the Air (OTA)

I have a Lolin NodeMCU V3 with a broken USB port: no power, no data. It does show up on WIFI as AI-thinker_xxx, I can connect, but what can I do next? Is there a way to program the NodeMCU Over the ...
1
vote
2answers
18k views

How to post HTTP POST requests on my website?

I am working on a NodeMCU board to post sensor data on my website service. Basically my project is about POST and GET requests both in single code. I am succeeding in sending GET requests from my ...
0
votes
0answers
10 views

nodemcu nack error bh1750

I am trying to run a simple example of bh1750 on my nodemcu, code is #include <Wire.h> #include <BH1750.h> */ BH1750 lightMeter(0x23); void setup(){ Serial.begin(9600); Wire.begin(...
0
votes
1answer
13 views

command keeps echoing because web page tries refreshing

I want to execute a action only once when I press web page button but as the page tries refreshing the action gets executed in a loop. I am using the wifimanualwebserver example for esp8266. Please ...
0
votes
0answers
39 views

Need sugestion to improve my arduino sketch

I want my code to blynk friendly by avoiding while condition in loop or flood error as mention by blynk. But , i m unable to do so.whenever i try to call function outside loop , it get stuck in first ...
0
votes
2answers
19 views

Temperature anomaly on BS18B20 + NodeMCU on Tingspeak

Temperature drops occasionally from 59+C to -13C or to other random values. Used sketch and info from this site: http://internetofthinking.blogspot.com/2016/02/upload-ds18b20-temperature-sensor-data....
0
votes
0answers
21 views

Nodemcu & GSM module & CLIP problem (CLIP line not always appears on the serial connection)

I'm working on phone-controlled car park gate. Trusted employees numbers are saved on SIM card/hard coded in program. So the idea is, if a trusted person calls the "gate number" ; Nodemcu will ...
0
votes
1answer
29 views

ESP12E motorshield analogWrite issue when powering DC motor

I am relatively new to adruino and this whole space. I am currently trying to power a DC motor using an ESP12E motor shield and an ESP8266 Module Motor Shield - https://www.amazon.com/gp/product/...
0
votes
0answers
19 views

Not able to interface BME280 with Nodemcu v3

I am not able to read bme280 sensor values and have tried many codes online. Please have a look below- code:- #include <Wire.h> #include <Adafruit_Sensor.h> #include <Adafruit_BME280....
0
votes
0answers
21 views

WS2812B not fully working with NodeMCUv2 [ESP8266]

I have a problem with my NodeMCU v2 board and my WS2812B led matrix with 256 (32x8) LEDs. The Board cannot be able to turn on the 191th led and stops working after the 190th without changing the ...
0
votes
0answers
26 views

NodeMcu does not connect to my wifi

this is the code , and it never connects to the wifi ,i dont know what to do , the code is an example in the blynk library
0
votes
0answers
32 views

Arduino How to Concat Strings

am stuck with something simple which is concating string not sure what am doing wrong , am getting exception (3 ) error due to it 3 LoadStoreErrorCause Processor internal physical address or data ...
0
votes
2answers
81 views

Nodemcu is connected to 5v relay with logic converter but still not working

I am using a bi-directional 3.3-5V logic converter to control 5V relay with 3.3V D5 pin of nodemcu. link of logic converter is here However, I expected to control the relay but it didn't work. I don'...
0
votes
0answers
22 views

NodeMCU current consumption in all modes

I am using NodeMCU for my project.I wanted to know how much current it takes in its all modes like sleep mode,deep sleep mode and also in its wifi modes like station and access point mode. Thanks in ...
0
votes
0answers
22 views

HX711 with NodeMcu

I am trying to make a scale that measuring weight. In internet i did some researches so i got some questions. I have this module as a HX711 And square 3 wired loadcells( Red,White,Black Wired). My ...
0
votes
0answers
13 views

3 wired loadcell with HX711 Arduino Uno, Nodemcu

I am trying interact with a loadcell that is 3 wired. I am using arduino uno or nodemcu adafruit huzzah and sparkfund hx711 module.But i cant take scales. I only getting 0.0 grams and when i applied ...
0
votes
0answers
107 views

Programming OMRON - D6T MEMS Thermal Sensor with NodeMCU

Hi I need some help here, I'm currently doing a school project that requires us to replace Arduino Uno to NodeMCU, I understand the hardware pin configuration is different, and I also found a code ...
0
votes
0answers
19 views

Connect NODEMCU with SIM800L

How should I connect nodemcu with sim800l? Will the code be similar to the one used for interfacing sim800l with arduino uno? I tried to use the GPIO pins 1 and 3. #include <SoftwareSerial.h> ...
0
votes
0answers
26 views

Nodemcu single server with 2 clients

I am trying to connect my nodemcu server with 2 nodemcu clients. One client is connected and it works perfectly. I am unable to configure what to do for the other client to be connected and share data ...
0
votes
1answer
23 views

Communication between three NodeMCUs such that one in in AP mode, second one in AP+STA mode and the third NodeMCU in STA mode

I am able to establish a connection between first and second NodeMCU, but unable to do so for the third nodeMCU. I used the IP address to establish connection. Should I assign a different IP to each ...
0
votes
0answers
55 views

ESP8266 do not 'reset' when I connected D0-RST for deepSleep

I connected like this status(D0 ~ RST) on my ESP8266 NODEMCU board for making deepSleep & wakeup automatically. after I set like this, ESP.deepSleep(5e6); // 5second for entering deepSleep mode ...
0
votes
0answers
27 views

How to make watchdog and automatically reset on esp8266

When my system is confronting at logical & hardwaretical problem, I want to make system know It has some problem and reset automatically because my esp8266(nodeMCU) is on the place where people ...
0
votes
0answers
19 views

Nodemcu POST Response “-1”

Nodemcu device is returning HTTP response -1 for a POST request on django rest api. I tried the below http request to Postman, and it works perfectly fine. http://localhost:8000/api/datalogs/?plant=...
0
votes
0answers
27 views

NodeMCU v2 - Current when powering from VIN

I am working on a project and I want to directly power my NodeMCU from VIN. I have found lots of articles and questions talking about different voltages on the VIN pin of the NodeMCU, but almost none ...
0
votes
0answers
319 views

WebSocketsServer.h: No such file or directory

I'm trying use the NodeMCU WebSocket. I downloaded the required libraries from: https://github.com/Links2004/arduinoWebSockets and pasted them in my Arduino libraries folder. I uploaded my code but ...
0
votes
0answers
21 views

Adafruit MQTT Library Error Connection failed

Adafruit_MQTT library is awesome but i have got a problem with it. I use it in Arduino with NodeMCU (ESP8266). Everything is okey with example code. (TLS connection - WiFiClientSecure). With my way ...
0
votes
0answers
42 views

DHT11 sensor reporting all null values

I am using a DHT11 sensor attached to a NodeMCU ESP8266 to have a web server reporting the local humidity and temperature values. I don't have a resistor attached in the circuit, the DHT11 is directly ...
0
votes
0answers
27 views

Can I use an RF Receiver to any pin on an Arduino?

I have a project that uses a nodemcu and it includes an rf receiver, I created the pcb board already etc etc... so I've already chosen D7 (GPI013) before reading on connecting the rf receiver and ...
0
votes
0answers
162 views

Wemos D1 won't work with MH-Z19B (CO2 sensor)

I would like to connect a CO2 sensor to the Wemos D1. I would like it to work via UART (RX, TX) and not the PWM pin. I've encountered numerous libraries on Github, but I can't seem to get it working. ...
0
votes
0answers
44 views

Why am I getting an 'invalid conversion' error on compile?

I have one of these NodeMCU ESP8266 OLED Arduino Wifi Modules which I am trying to load with SpaceHuhn's deauther software from Github I am trying to compile the source code using Arduino IDE with ...
0
votes
0answers
22 views

About split string

Sorry my English is poor. I use nodemcu to get a json data. By this String alldata = client.readString(); But it turn this: HTTP/1.1 200 OK Server: nginx Date: Sat, 10 Aug 2019 04:53:16 GMT ...