Questions tagged [nodemcu]
For questions about the NodeMCU open-source Internet of Things (IoT) platform. Use in conjunction with the "iot" tag.
179
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NodeMCU / ESP8266 died
I created the attached circuit. It's about as simple as it gets, 4 buttons (2 low since GPIO pins are pulled up, and 2 high or low depending on whether they're pressed), a stepper motor controller, ...
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How to protect a relay from power surge?
simulate this circuit – Schematic created using CircuitLab
I am trying to control an LED bulb using a solid-state relay, the problem is, the bulb is flickering from time to time, if it is turned ...
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2
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95
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Controlling LEDs with MOSFETs
I am working on a hobby project in which I am controlling two rows of LEDs. Each row has 5 LEDs in series. I want to achieve the logic drawn in this table:
Can anyone suggest any MOSFET logic to ...
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114
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Why am I getting 255 for all NPK values?
I am using a NodeMCU ESP8266 WiFi board for collecting N - P - K sensor data. I am using RS485 as interface.
This is the code:
...
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35
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NodeMCU/ESP8266 with 2 relays doesn't work
I have the schematics below in which one of the relays work fine but the other doesn't, from design perspective they are the same!
The relay at the bottom is the one that is not working:
And this is ...
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40
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Modbus RTU on ESP8266 to control VFD
Hoping to get some help on setting up a NodeMCU (esp8266) with this 1 arduino library to control a Variable Frequency Drive (VFD).
I'm afraid to say that I almost need help from square one, as I'm ...
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2
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171
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Where is the flash memory on the NodeMCU ESP8266 v3?
In the NodeMCU v3 specs it says it has 4Mb flash memory. In the ESP-12EX datasheet it says the MCU has no rom, but can boot from an SPI external memory.
However, I don't see any flash memory chip on ...
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176
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Why does the DS18B20 temperature sensor require a stronger pull-up resistor when Node MCU is powered through the Vin pin?
I have a DS18B20 temperature sensor connected to a Node MCU (ESP-12 / ESP8266) like shown below, where μP is the MCU (any GPIO gives the same result) and Vpu = VDD = 3.3 V, coming from the 3.3 V pin ...
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Will L7806 work with NodeMCU?
I have a NodeMCU LUA Lolin V3 with an ESP8266 -12E.
I want to know if I can use an L7806CV votage regulator with it through the VIN pin?
The NodeMCU has an AMS1117 3.3 voltage regulator.
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137
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How to control my DOL starter buttons (ON and OFF) with NodeMCU of my 1.5 hp motor (motor starter/panel) to control it remotely?
I have been working on an IoT project at home. I have three different tanks with different volumes of water in them. I want to have the levels displayed on my dashboard using a Raspberry Pi. I need to ...
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186
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Powering ESP32S Node MCU through Vin vs USB
I am having a situation with my ESP32S Node MCU that I can't figure out.
I uploaded a sketch to my MCU that will blink the blue LED connected to GPIO 2 every x number of seconds.
Here is the sketch
<...
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52
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Driving LED light chain that needs voltage switching
I have some LED party lights with a defect controller. If you power it "+/-", only the odd ones are illuminating, on "-/+" only the even ones.
Now I want to drive them using a ...
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66
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NodeMCU v3 with TIP120 and DC booster
I have already been through plenty of topics to try to integrate three TIP120s with a DC booster in order to operate two solenoids valves (non-latching NC ones). I think I am getting close but there ...
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55
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How can I test WS2812B 5 m 60 LEDs/m with NodeMCU?
I bought this WS2812B 5 m 60 LEDs/m. I want to know if it works properly. I have a NodeMCU 1.0 and I recently bought a 5 V, 10 A adaptor for these but the damn thing still only lights up the first LED ...
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274
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How to use an MPU 6050 (or any I2C) on different pins on an NodeMCU?
My idea was to have multiple MPU 6050 (6-DOF accelerometer) sensors connected and read by an NodeMCU. I had tested a single accelerometer on the D1, D2 pins and it ...
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Does running the ESP8266 or any other MCU below the minimum voltage cause damage?
I'm powering an ESP8266 MCU from a 2.5V voltage source that occasionally drops to 2V when a motor runs (runs for about 5 seconds twice a day). The battery is low. Incidentally, the MCU is powering a ...
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116
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Why is this NodeMCU acting like this?
I am experimenting with a NodeMCU. I want to use a push button to give input to the microcontroller. My setup is as follows:
simulate this circuit – Schematic created using CircuitLab
The ...
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78
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BME280 sensor locks ESP8266 and prevents booting
I have an AZDelivery Node MCU ESP8266 linked via SPI to a Adafruit BME280 Temperature, Humidity and Pressure Sensor that when the data connections are made it prevents the ESP from booting and ...
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31
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NodeMCU RF522 connection not working
I have a NodeMCU which is connected to a RF522 sensor and a LCD display.
I did the connection as follows
D4-SDA
D5-SCK
D7-MOSI
D6-MISO
GND-GND
RST-D3
3V-3.3V
LCD-I2C is connected nodeMCU as:
GND-GND
...
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1
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16
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NodeMCU 12E power requirement
On the back of the NodeMCU, it is: Vin +5V Recommended +10V MAX. I can see that it has an AMS1117 voltage regulator. Its datasheet says we can use [4.5V to 15V]
...
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92
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Can't connect to a NodeMCU ESP8266
I have a bunch of NodeMCU ESP8266 boards (bought three from here: https://www.amazon.ca/gp/product/B07HF44GBT/), but for the life of me I can't figure out how to actually use them.
When I plug them in ...
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455
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ESP32 2 SPI connnection ethernet shield and usb host
Is it possible to have two SPI connection for ESP32
for ESP32 below link for the product
https://www.amazon.co.uk/AZDelivery-NodeMCU-CP2102-Development-Parent/dp/B07ZZFXRTY
for ethernet shield
...
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2
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113
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Is it important to which GND I connect my relay (OR gate on signals from two different controllers with separate VINs)
I have a power supply (let's say 5V battery) and a NodeMCU (micro-controller) attached to it.
I want to turn on the power supply for this NodeMCU #1 by signal from another micro-controller (from ...
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76
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NodeMcu (ESP8266) pinout problem
I am trying to use a nodeMcu in a project that involves:
a microSD card reader (SPI),
two devices that communicate with nodeMcu via software serial,
a switch
and 2 leds.
Currently the microSD is ...
- 101
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64
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1
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1
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77
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Connecting optocouplers to pins D3 or D4
I am trying to create a fairly standard setup: controlling 4 channel relay with NodeMCU.
I decided to use optocouplers to make connections and generally have everything working now. However I learned ...
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2
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134
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Nodemcu: How to extend sensor wires?
I am using a Water flow sensor connected to v2 nodemcu. However, this sensor needs to be placed at a distance of 40 feets from nodemcu, on the 3rd floor of my apartment roof (I stay on 1st floor).
The ...
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how to detect water level using NodeMCU in overhead tank?
I am making a simple water level alarm connected to my V2 NodeMCU. Using the principle of water conductivity.
Two wires with stripped ends are dipped into the tank. As soon as the water level reaches ...
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322
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Providing power to NodeMCU (ESP 8266) from 5V output of an Arduino
Is it possible to power a NodeMCU from 5V output of an Arduino UNO board? I was trying to use the Vin of the NodeMCU as the input from the 5V port of the Arduino. It didn't work. Could anybody please ...
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LED_BUILTIN output is not working on NodeMCU ESP8266
I have a new NodeMCU ESP8266. I made sure that the builtin LED on it was working properly by uploading the "Blink" example sketch from the Arduino IDE examples and it worked. When I try my ...
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112
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What GPIOs in NodeMCU are usable
I am running out of usable GPIOs in my NodeMCU esp8266 board. I'm making a car. For the car I use L298N motor driver with 4 gear motors. The pins of L298N motor driver is connected as like this,
1.ENA ...
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308
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Powering this circuit off 3A USB charger, but it's only supplying 350mA
I have a very simple circuit for a small RGB lamp I'm building. My plan was to power it off one of my many spare old USB phone chargers via micro-usb. It's just a string of 60 WS2812B LEDs with a ...
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332
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How long can I power up a nodeMCU
I have a nodeMCU esp8266 and I'm going to power up the nodeMCU as long as possible but I need to know is it good to the health of nodeMCU. In other way I am going to power the nodeMCU forever.(...
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1k
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Can I power a nodeMCU using 3.7 battery
I have a nodeMCU board (3.3V) and a li-ion battery with 3.7 V. Is it alright to give the power supply from that battery?
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290
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Wire gauge for sensor at long distance
I am planning for a home irrigation system and confused with the wire gauge required the sensors on the plants.
The circuit diagram would be something like below: (Please consider the sensors as ...
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108
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Understanding what exactly is the NodeMCU
So the NodeMCU looks like this:
And the ESP12 is this:
So I can see that the little ESP12 is riding on the NodeMCU.
my question is: What is included in the ESP12 and what in the NodeMCU, in context ...
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919
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Power NodeMCU from Arduino Uno
I am facing challenge in powering up NodeMCU from Arduino.
My Arduino is connected with external power supply (12v). From Arduino, I connected 5vpin to NodeMCU <...
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2k
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ESP-01 module CH_EN pin confusion
I have a custom board that I have developed where I am using the ESP-01 module.
I have not connected the CH_EN pin to GND or Vcc on the board. When I connect the module to the board, the red LED ...
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37
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NodeMCU http calls failing
I am trying to communicate between 2nodemcu v2, standalone everything works fine - webserver, api etc. but when I start communicating between both devices only first API hit works thereafter it ...
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116
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How to find mAh rating of battery for my project?
I am using a NodeMCU ESP8266 for my project.
The datasheet says it consumes 170 mA in active mode, and approximately 10 milliamperes in sleep mode.
In my project, the NodeMCU runs 1 minute in active ...
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2
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215
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Relay not getting triggered from NodeMCU high
Please bear with me since am a noob in electronics. I made a relay module based on internet DIY tutorials. It turns on when I provide 5V from adapter to both +5V and signal but when I supply high of ...
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55
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MOSFET N loss power battery calculation
I have a circuit to calculate my battery level using NodeMCU.
I use this formula:
...
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170
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Adding momentary switch (push-button) to NodeMCU
I want to add 2-pole momentary push-button (switch) for my covers.
Integration goes through a NodeMCU and ESPHome.
I'm having a hard time understanding the schematics for this switch:
I'm not sure ...
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158
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NodeMCU/ESP8266 to drive pulse sensor?
I have a Daikin BRP069A61, which is a heatpump accessory that allows the heatpump te smartgrid controlled. In simple terms: It will turn on when PV-power is available and will limit power to whatever ...
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1
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915
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Stepper motor driver TMC2209 is powered from microcontroller logic pins
I am doing my first steps with a TMC2209 V1.2 stepper motor driver and a NodeMCU.
This is my circuit:
I power the motor side via 12 V supply (12 V on the lower rails). In the circuit, this is ...
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2
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1k
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Dual Power Supply for single 10m LED Strip Run
This is my first time here so sorry for any wrong formatting.
I am currently creating a project where I will run my wall with 10 meters of addressable LED strip (Made up of 2 x 5 meters rolls). I have ...
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49
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How to know the status of a two way switch through MCU
My project is this one that I asked earlier (except the fact that I'll be using SPDT switches) Two way lighting
What I'm asking can the MCU detect if the circuit is closed (whether by the physical ...
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1
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288
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Pull 5V using NodeMCU output pins
This diagram is of the little device to read the data from P1 port on the DSMR electric meter. In my case it is Landis E360.
RTS and 5V pins are shorted in the diagram and that is to trigger the data ...
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395
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Cannot flash Wemos D1 using NodeMCU
I am trying to flash Wemos D1 mini (ESP8266) using NodeMCU according to this video. Pins NodeMCU → Wemos:
RX → RX
TX → TX
D3 → D3
RST → RST
3.3V → 3.3V
GND → GND
EN → GND
When flashing Wemos LED is ...
- 101
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209
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How to wire MCU control signals with power and ground to control multiple external motors?
I'm working on a system based on a NodeMCU/ESP8266 WiFi controller, which controls two separate motor units, each consisting of a 12V motor and solenoid actuator. For practical reasons, I need to ...
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