Questions tagged [nodemcu]
For questions about the NodeMCU open-source Internet of Things (IoT) platform. Use in conjunction with the "iot" tag.
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PT100 sensor for measuring liquid resin, fully submerged
Edited
Link to Pt100 sensor (That's the best i could do)
https://www.intech.co.nz/products/temperature/mrh.html
Link to ESP8266 datasheet
http://www.handsontec.com/pdf_learn/esp8266-V10.pdf
...
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MCP23017 with NODEMCU v3 (lolin) I2C doesn't work
I want to use NodeMCU v3 with a MCP23017 that has a MAX6675 at the end. Everything is in the circuit; please see the image.
The MAX6675 (U3) doesn't want to work with the MCP23017.
First MAX6675 (U4) ...
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Powering NodeMCU
I am trying to power a NODEMCU board using a battery. I am using a TLV713P to regulate the voltage. Can I power a nodeMCU ESP32 board using this regulated voltage by giving it to the 3V3 pin?
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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 ...
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3
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Emergency backup battery supply
I am building a NodeMCU-controlled 12 V solenoid. I am hoping to add an emergency backup battery supply, but the emergency backup supply should not power anything but the solenoid. In other words, if ...
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Issues with Nodemcu, LoRa Module (Lora-02), and Bluetooth Module (Hc-05) for SMS Communication
I am currently working on a project that involves using an node mcu, a LoRa module (Lora-02), and a Bluetooth module (HC-05) to enable the transmission of free SMS between two mobile devices when ...
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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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Trying to get (more) accurate readings from thermistor (electronics, math, and code inside)
So I'm trying to get accurate temperature readings off this TDK B57164K472J thermistor...
It's connected in series with a 1 K resistor, and connected to an ESP8266's onboard ADC.
The thermistor has a ...
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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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NodeMCU power via battery + battery charger + booster
I need to power a NodeMCU (as far as I know it can work with 3v3 but I use some I2C modules that need 5V so let's power everything with 5V.)
I have a Li-ion battery (3.7V.)
I have a TP5046 based ...
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TP4056 - Micro USB 5V 1A - Output pins Current supply
I have "TP4056 - Micro USB 5V 1A Lithium Battery Charger with Protection" as below
I have a Li-Ion 3000mAH battery like below
Connected them as below
Questions:
What is the maximum current that I ...
CommunityBot
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Controlling servo with MOSFET [duplicate]
I'm trying to understand how to drive a servo that needs 5 V power with a 3.3 V output microcontroller. If I have a 3.3 V PWM signal and a 5 V power source, is there a way that I can use a single N-...
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TPL5110 doesn't work with NodeMCU
I am using a TPL5110 timer to drive my NodeMCU, in order to keep battery consumption low, but I can't let it work.
I have setup the standard circuit for this timer, as below:
Whenever I apply power ...
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3
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How to connect WS2812B strips to all show same animation?
I have a 3 meter WS2812B strip that I want to connect to a NodeMCU in a very specific way.
I want to cut the strip down to six 20 cm segments but I don't want the animations to "snake" from ...
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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 ...
CommunityBot
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AC 230V voltage line detection with Sharp PC814 switch (home automation)
I want to use home automation, so I am thinking of using an input to an ESP8266 from a PC814 bi-directional optocoupler for a 230 VAC mains physical switch.
Using this scheme I don't have to modify my ...
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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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Issue with my solar charger using LM2596
I am using a 20W solar panel, maximum voltage 21V & maximum current 1.23 A. I am using LM2596 to dtep-down to 5V to charge my powerbank, hich will later power my Nodemcu (ESP8266 board.)
Issue in ...
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As in the picture when I connect the gnd of hlw8012 to the gnd of esp8266 I get electric shock .what should I do now
I'm working on a project based on Iot so I was using hlw8012 for power monitoring and after connecting the IC module to the esp8266 whenever I touch the Esp module I get electric shock . What should I ...
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Remove ESP8266 from NodeMCU board
I want a simple programming jig for the ESP8266. Sadly, all of the jigs I can find on eBay and other sites have not worked for me. I use the Silicon Labs CP210x, and I have had NO luck at all with ...
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How to get a constant 5 V power supply when using the same power supply for motors and micro controllers
I have made a WiFi controlled car using NodeMCU. It works fine if I connect the NodeMCU to a separate 5 V supply.
If I use the same power supply for both the motors and the NodeMCU, it resets ...
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SIM800C GSM module works via PC but not on battery
Before giving the specifications of my project, I'd like to say that I'm a total beginner in electronics but I do have a background in IT development.
I also want to apologize if this question has ...
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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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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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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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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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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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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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ESP32 using acs712 give wrong values
I'm trying to measure current with acs712 30A current sensor connecting to NodeMCU-32S but I'm getting wrong and unstable values. For zero current the ADC pin should read value of 2048 (esp has 12 bit ...
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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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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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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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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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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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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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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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Resetting of NodeMCU ESP8266 in deep sleep
I have been doing a project as my first project to learn ESP8266 applications. My project is a temperature and humidity values data logger and upload the data to Thingspeak.
The sensor used is DHT11.
...
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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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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
...
- 6,162
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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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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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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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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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Calculating Yaw Pitch and Roll from Quaternions in MPU6050 without Gimbal lock but giving problems
I am trying to convert quaternions provided by a MPU6050 to heading attitude and bank values but at least one of the three calculations is broken, for example in the third calculation (the uncommented ...
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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 ...
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