Prepare ESP32 with CP2102 Driver and nanoFramework

1. Use the Correct USB Cable

Make sure you’re using a proper data USB cable. Some USB cables are power-only and won’t allow communication with your ESP32 board.

2. Check Device Manager

Open Device Manager and look under Other devices.
You may find your ESP32 listed as:

CP2102 USB to UART Bridge Controller

3. Download the CP210x Driver

Go to the Silicon Labs driver page: https://www.silabs.com/software-and-tools/usb-to-uart-bridge-vcp-drivers?tab=downloads

Download the appropriate driver for your system:

Tip: Check the Tech Docs tab for release notes before installing:
https://www.silabs.com/software-and-tools/usb-to-uart-bridge-vcp-drivers?tab=documentation

4. Install the Driver

On extracting the contents you will find a release notes file (eg: CP210x_Universal_Windows_Driver_ReleaseNotes.txt) within which are instructions on how to go about installing the driver.

Follow the OS specific installation instructions therein.

4.1. On windows

For the ‘CP210x_Universal_Windows_Driver’ driver, it’s as simple as:

silabser.inf -> Right-click -> Install

After installation, go back to Device Manager.

Under Ports (COM & LPT), you should now see:

Silicon Labs CP210x USB to UART Bridge (COMx)

Installing nanoFramework on ESP32

5. Install ESP Tool to erase device (Optional)

This is optional, but most likely will come in handy when you want to do a thorough erase of the ESP device. You need to have Python installed and we will have this tool installed via pip.

pip install esptool

And now to erase the device.

esptool --port COM7 erase-flash

Identify your COM port from Device Manager (e.g., COM7).

ref: https://docs.espressif.com/projects/esptool/en/latest/esp32/

6. Install nanoFramework Flasher Tool

Install the nanoff tool globally:

dotnet tool install -g nanoff

Verify installation:

nanoff --version

7. Flash nanoFramework Firmware

Identify your COM port from Device Manager (e.g., COM7).

Run:

nanoff --platform esp32 --serialport COM7 --update

Replace COM7 with your actual port.

It might help including --target <ESP_Package>. eg: --target ESP32_S3.

You may fetch your device details using:

nanoff --serialport COM7 --devicedetails

You may list available targets using:

nanoff --listtargets

8. Fix .NET Runtime Error (If Required)

If you see an error like:

You must install or update .NET to run this application.

App: C:\Users\rohza\.dotnet\tools\nanoff.exe
Architecture: x64
Framework: 'Microsoft.NETCore.App', version '8.0.0' (x64)

Scroll down in the error message and open the provided link, for example:

To install missing framework, download:
https://aka.ms/dotnet-core-applaunch?framework=Microsoft.NETCore.App&framework_version=8.0.0&arch=x64&rid=win-x64&os=win10

Download and install the required .NET runtime, then rerun the flash command.

nanoff --platform esp32 --serialport COM7 --update

9. Boot Mode (If Flashing Fails)

Some ESP32 boards require entering boot mode manually:

1. Press and hold the BOOT button
2. While holding, start the flashing command
3. Release the button after flashing begins

10. Bonus - Updates

You might receive NuGet updates when working on a project and upgrading them will lose parity with the Nano Framework version on your device. These below commands will help you update the device.

List dotnet globally installed tools

In case, it’s been a while and you might have uninstalled Nano or it isn’t globally installed.

dotnet tool list -g

Find nanoff version

nanoff --version

Update nano

dotnet tool update -g nanoff

Flash device with latest

Optional, but I recommend you erase the device entirely before updating the firmware.

esptool --port COM7 erase-flash

And here the update command:

nanoff --platform esp32 --serialport COM7 --update