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Hedy

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How to Get HEX from Arduino?

#hex #arduino #arduinoide #stm32

There are several ways to get the compiled HEX file from Arduino IDE or platform. Here are the most common methods:

Image description

Method 1: Using Arduino IDE (Easiest Way)
For AVR Boards (Arduino Uno, Nano, Mega)

  1. Enable Verbose Output
  • Go to File > Preferences
  • Check "Show verbose output during compilation"
  1. Compile the Sketch (Ctrl + R or Sketch > Verify/Compile)
  • The IDE will display the temporary build folder path in the console.
  • Look for a line like: 
C:\Users\YourUser\AppData\Local\Temp\arduino_build_123456/YourSketch.ino.hex
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  1. Manually Copy the HEX File

Navigate to the temporary folder and copy the .hex file.

For ARM Boards (Arduino Due, Zero, MKR)
ARM-based boards generate .bin files instead of .hex.

  • The file is located in the same temporary folder (look for *.bin).
  • You can flash it using BOSSAC or OpenOCD.

Method 2: Using Arduino CLI (Advanced)
If you prefer command-line tools:

sh
arduino-cli compile --fqbn arduino:avr:uno YourSketch.ino --output-dir ./output
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The .hex file will be saved in the ./output folder.

Method 3: Using PlatformIO (Best for Advanced Users)

  1. Compile the Project 
sh
pio run
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  1. Find the HEX File

Located in:

.pio/build/your_board/firmware.hex
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Method 4: Manually Dumping HEX from a Programmed Arduino
If you need to extract HEX from an already programmed Arduino(What is Arduino?):

Using avrdude (AVR Boards)

sh
avrdude -p atmega328p -c arduino -P COM3 -b 115200 -U flash:r:backup.hex:i
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  • Replace COM3 with your Arduino's port.
  • This reads the flash memory into backup.hex.

Using STM32CubeProgrammer (STM32 Boards)

  1. Connect via ST-Link or USB DFU.
  2. Read memory and export as HEX.

How to Use the HEX File
AVRDUDE: Flash using:

sh
avrdude -p atmega328p -c usbasp -U flash:w:your_file.hex:i
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STM32CubeProgrammer: For ARM-based boards.

XLoader: Simple GUI for uploading HEX to AVR.

Why Extract the HEX File?
✔ Direct flashing without Arduino IDE
✔ Mass production programming
✔ Reverse engineering (for educational purposes)

Top comments (1)

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abdelwahid_nejmeddine_7b0 profile image
Abdelwahid Nejmeddine •

To get a HEX file from an Arduino sketch, follow one of these methods depending on your setup:

Method 1: Using Arduino IDE (Standard method)

  1. Open your sketch in the Arduino IDE.

  2. Compile it by clicking the checkmark (Verify) button.

  3. Locate the temporary build folder:

Go to File > Preferences.

Enable "Show verbose output during: compilation".

Click Verify again.

Look at the output panel below — it will show the full path to the .hex file, something like:

.../AppData/Local/Temp/arduino_build_xxxxxx/your_sketch.ino.hex

  1. Copy the file from that temporary folder to a safe location.

Method 2: Using Arduino CLI

If you prefer terminal tools:

  1. Install Arduino CLI.

  2. Run:

arduino-cli compile --fqbn arduino:avr:uno your_sketch

  1. This generates a .hex file in the build directory.

Method 3: From PlatformIO (VS Code)

If you're using PlatformIO in VS Code:

  1. Build your project.

  2. The HEX file is generated in:

.pio/build/your_board/firmware.hex

Do you need the HEX file to upload it using another programmer or tool? I can guide you with that too.