ESP8266 ADC – Read Analog Values with Arduino IDE, MicroPython and Lua
MicroPython and Lua Both the ESP8266-12E and the ESP8266-07 have an easy-to-reach ADC pin. This means that the analogue signals can be read by these ESP8266 boards. In this tutorial, we'l…
Know the mission before touching a wire.
Understand what you are making, prepare the right tools, and make the workbench safe.
Project details
ESP8266 ADC – Read Analog Values with Arduino IDE, MicroPython and Lua is a iot project. MicroPython and Lua Both the ESP8266-12E and the ESP8266-07 have an easy-to-reach ADC pin. This means that the analogue signals can be read by these ESP8266 boards. In this tutorial, we'l…
- Source pages
- 1031-1034
- Named parts
- 5
- Build goal
- Working, tested prototype
Tools you need
- Digital multimeter
- Wire stripper and side cutters
- Soldering iron with a fine tip
- Current-limited bench supply
- Computer with a data-capable USB cable
Use eye protection, good lighting, and a clean insulated surface throughout the build.
Safety precautions
- Disconnect every power source before changing a connection.
- Check component polarity, pinout, and supply voltage twice.
- Use a current limit for the first power-up.
- Keep liquids, loose metal, and uninsulated wires away from the bench.
Gather, identify, and understand every part.
Use the standardized inventory, then open What's this? to learn each part's role, advantages, limitations, handling, and specifications.
What's this?Image, role, pros, cons, handling & specifications
MODULE LEARNING VIEWESP8266-12E NodeMCU Kit is suggested (read ESP8266
A programmable controller that reads inputs, makes decisions, and drives the project's outputs.
What it does hereIt is the control centre and must use the documented board, pin map, supply, and logic level.
Buy / compare this part ↗Advantages
- Reprogrammable and reusable
- Large learning ecosystem
- Complex behaviour remains changeable
Limitations
- GPIO voltage and current are limited
- Some pins affect boot or communication
- Loads normally need a driver
Handling
- Disconnect power before rewiring
- Avoid static discharge
- Never power motors, relays, or pumps directly from GPIO
Specifications to verify
- Use the exact model, value, package, and rating listed for ESP8266-12E NodeMCU Kit is suggested (read ESP8266; similar-looking parts are not always interchangeable.
- Confirm operating voltage, logic level, pinout, memory, USB interface, and maximum GPIO current.
What's this?Image, role, pros, cons, handling & specifications
development boards comparison)
A named project component whose exact role is defined by the source circuit and build guide.
What it does hereIt performs a documented electrical, control, interface, or construction function in this project.
Buy / compare this part ↗Advantages
- Selected for this project
- Can be checked independently
- Supports modular troubleshooting
Limitations
- Substitutes may differ
- Generic names can hide variants
- Pinouts and ratings vary
Handling
- Compare the received part with the source
- Keep it labelled
- Do not force connectors or adjusters
Specifications to verify
- Use the exact model, value, package, and rating listed for development boards comparison); similar-looking parts are not always interchangeable.
- Confirm dimensions, ratings, connection method, polarity, and environmental limits.
What's this?Image, role, pros, cons, handling & specifications
x ESP8266-07 chip or 1x ESP8266-12E chip plus an FTDI
A programmable controller that reads inputs, makes decisions, and drives the project's outputs.
What it does hereIt is the control centre and must use the documented board, pin map, supply, and logic level.
Buy / compare this part ↗Advantages
- Reprogrammable and reusable
- Large learning ecosystem
- Complex behaviour remains changeable
Limitations
- GPIO voltage and current are limited
- Some pins affect boot or communication
- Loads normally need a driver
Handling
- Disconnect power before rewiring
- Avoid static discharge
- Never power motors, relays, or pumps directly from GPIO
Specifications to verify
- Use the exact model, value, package, and rating listed for x ESP8266-07 chip or 1x ESP8266-12E chip plus an FTDI; similar-looking parts are not always interchangeable.
- Confirm operating voltage, logic level, pinout, memory, USB interface, and maximum GPIO current.
What's this?Image, role, pros, cons, handling & specifications
Potentiometer
A named project component whose exact role is defined by the source circuit and build guide.
What it does hereIt performs a documented electrical, control, interface, or construction function in this project.
Buy / compare this part ↗Advantages
- Selected for this project
- Can be checked independently
- Supports modular troubleshooting
Limitations
- Substitutes may differ
- Generic names can hide variants
- Pinouts and ratings vary
Handling
- Compare the received part with the source
- Keep it labelled
- Do not force connectors or adjusters
Specifications to verify
- Use the exact model, value, package, and rating listed for Potentiometer; similar-looking parts are not always interchangeable.
- Confirm dimensions, ratings, connection method, polarity, and environmental limits.
What's this?Image, role, pros, cons, handling & specifications
Breadboard, Switchers
A named project component whose exact role is defined by the source circuit and build guide.
What it does hereIt performs a documented electrical, control, interface, or construction function in this project.
Buy / compare this part ↗Advantages
- Selected for this project
- Can be checked independently
- Supports modular troubleshooting
Limitations
- Substitutes may differ
- Generic names can hide variants
- Pinouts and ratings vary
Handling
- Compare the received part with the source
- Keep it labelled
- Do not force connectors or adjusters
Specifications to verify
- Use the exact model, value, package, and rating listed for Breadboard, Switchers; similar-looking parts are not always interchangeable.
- Confirm dimensions, ratings, connection method, polarity, and environmental limits.
Connect one verified path at a time.
Explore the named components and standardized signal flow, then use Source Check to verify exact physical pins, values, and topology before applying power.
Trace this circuit.
ESP8266 ADC – Read Analog Values with Arduino IDE, MicroPython and Lua: interactive parts, standardized terminals, responsive anchored wires, student explanations, and the original circuit reference in one shared system.
Trace before wiring
Follow power, ground, inputs, processing, and outputs in that order. Never guess a pin from package shape alone.
Connect with power off
Make short, labelled connections and share a common ground only where the schematic requires it.
Inspect every joint
Check continuity, polarity, adjacent shorts, and loose connections before the first power-up.
Open all source diagrams and build views 2 visuals
Confirm the hardware-only control path.
This project does not include firmware in the source. The circuit itself provides the required behaviour.
How to connect
- Match every controller label to the circuit view and source pin map.
- Join grounds before signal wires when separate low-voltage supplies are used.
- Keep motors, relays, pumps, and other loads on a suitable driver and external supply.
Common mistakes
Reversed VCC/GND, board-label versus GPIO-number confusion, missing common ground, and charge-only USB cables.
Troubleshoot
Disconnect loads, continuity-test one path at a time, then test with a current limit.
Software preparation
No IDE, board package, library, or firmware upload is required for this project.
If you add a programmable controller as an extension, document its pin map separately.
How to upload code
The original design is implemented entirely in hardware, so proceed after verifying the circuit and supply.
Assemble, deploy, test, and troubleshoot.
Use the complete source notes in build order, then pass the final checks before calling the project finished.
Build in functional stages
- Power and regulation
- Controller or processing stage
- Inputs and sensors
- Outputs and loads
- Enclosure and strain relief
Power up safely
- Inspect unpowered continuity first
- Apply the lowest safe current limit
- Measure supply rails before signals
- Add one load at a time
- Record expected and actual results
Work from simple to complex
- Confirm power, ground, polarity, and orientation
- Compare each pin with the source
- Test inputs separately from outputs
- Replace only one variable at a time
- Power off before every correction
Follow the documented instructions.
These notes come from this project's source and remain in their original order.
Project overview
Project build noteMicroPython and Lua
Both the ESP8266-12E and the ESP8266-07 have an easy-to-reach ADC pin. This means that the analogue signals can be read by these ESP8266 boards. In this tutorial, we'll show you how to use Arduino IDE, MicroPython, or Lua firmware to read analogue data from an ESP8266.
This project is divided in three sections
Project build note1. ESP8266 Analog Read with Arduino IDE 2. ESP8266 Analog Read with MicroPython 3. ESP8266 Analog Read with Lua/NodeMCU ESP8266 ADC Specifications When talking about the ESP8266 ADC pin, these terms are often used
interchangeably
Project build noteADC (Analog-to-digital Converter) TOUT Pin6 A0
Analog Pin 0 All these terms refer to the same pin in the ESP8266. ESP8266 ADC Resolution The 10-bit resolution of the ADC pin means that you can get values between 0 and 1023. ESP8266 Input Voltage Range If you are using the bare chip, you can put 0V to 1V on the ADC pins. But most ESP8266 development boards have a voltage divider built in, so the
input range is from 0V to 3.3V. So, in conclusion
Project build noteESP8266 Analog Pin With the ESP8266 12-E NodeMCU kit and other ESP8266 development boards, it's easy to get to the A0. Just connect a jumper wire to the pin.
Part Required
Project build noteESP8266-12E NodeMCU Kit is suggested (read ESP8266 development boards comparison) 1x ESP8266-07 chip or 1x ESP8266-12E chip plus an FTDI programmer is another option. If you are using a bare chip, you will need a 100 Ohm resistor. If you're using a bare chip, you'll need a 220 Ohm resistor. 1k Ohm Potentiometer Breadboard, Switchers
Schematic Diagram
Project build noteIf you are using an ESP8266 chip with an input voltage range of 0V to 1V, the input voltage on the A0 pin can't be more than 1V. So, you need a voltage divider circuit. Wrapping Up In this guide, we showed you how to use the ESP8266 analogue pin to read analogue values (A0). One important thing to remember is that the ESP8266 analogue input range is either 0-1V or 0-3.3V, depending on whether you're using a bare chip or a development board. No matter what, you should never go over the maximum voltage that is recommended. When you need a wider range of input voltage, you might want to add a voltage divider circuit.
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You followed the full workflow from understanding the mission to testing the finished project. That is a real engineering achievement - well done.
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