Externally-connected AirLift FeatherWing and Itsy breakouts have three optional ESP32 control pins which are not connected by default:

• ESPGPIO0
• ESPRX
• ESPTX

Other AirLift external breakouts have these pins already available.

Upload Passthrough Code

First, you'll need to upload the code below to allow your board to act as a programmer for the ESP32 AirLift module.

Back up any code and files on your CIRCUITPY drive. The code will overwrite the drive's contents. You should not end up losing any files on the QSPI flash, but it's a good idea to back them up anyways. 

Download the UF2 file for your board and save it to your computer's Desktop.

For Adafruit Feather RP2040, if you are not stacking a FeatherWing AirLift directly, connect these pins together:

• Feather D13 to Airlift CS
• Feather D12 to AirLift RST
• Feather D10 to AirLift GPIO0
• Feather TX to Airlift RX
• Feather RX to AirLift TX

For Raspberry Pi Pico, connect these pins together:

• Pico GPIO13 to Airlift CS
• Pico GPIO16 to AirLift RST
• Pico GPIO9 to AirLift GPIO0
• Pico GPIO0 (TX) to Airlift RX
• Pico GPIO1 (RX) to AirLift TX

To enter bootloader mode, start with your board unplugged from USB. Next, find the reset button on your board. It's a small, black button, and on most of the boards, it will be the only button available. 

To enter bootloader mode, start with your RP2040 board unplugged from USB.

Press and hold the BOOTSEL button (highlighted in red in the image of the Feather RP2040, but all RP2040 boards should include this button), continue to hold it while plugging it into USB, and wait for the RPI-RP2 drive to appear before releasing the button.

Find the .UF2 file you downloaded and drag that file to the new drive on your computer.

The board's LED should flash and the drive will disappear. Your board should re-enumerate USB and appear as a COM or Serial port on your computer. Make a note of the serial port by checking the Device Manager (Windows) or typing ls /dev/cu* or /dev/tty* (Mac or Linux) in a terminal.

Download NINA Firmware

Click the link below to download the latest version of the NINA firmware. Unzip it and save the .bin file to your desktop.

Next, you'll need to flash the firmware to your ESP32 AirLift module.

If you're using the Google Chrome browser or Microsoft Edge (version 89 or later), you may follow the instructions below for programming using your board.

For advanced users who have esptool.py installed, skip to the bottom of the page.

Upload NINA Firmware

Next, you'll need to upload the new version of NINA firmware to your ESP32 AirLift. To do this, we'll use the web-based implementation of the flasher tool for Espressif chips, ESPTool. You will need to be running Google Chrome or Microsoft Edge (version 89 or later) to follow the steps below.

Safari and Firefox, etc. are not supported because we need Web Serial and only Chrome is supporting it to the level needed. If you're using an unsupported browser, you'll need to either switch to Google Chrome or upload NINA firmware using the Python esptool.py program from your computer (Scroll down to Upload NINA Firmware with esptool.py,)

On your Google Chrome browser, navigate to https://adafruit.github.io/Adafruit_WebSerial_ESPTool/

Turn on the toggle labeled No reset for Passthrough updates:

In the top-right corner, select 115200 as the baud rate and click the Connect button.

You will get a pop-up asking you to select the board's COM or Serial port.

• If there are a lot of boards and ports appearing in this list and you're not sure what to select - remove all other USB devices so only your board is attached, that way there's no confusion over multiple ports! 

Click Connect.

Verify the New Firmware Version

To verify everything is working correctly, we'll load up some CircuitPython code. 

If you were previously using your ESP32 project with CircuitPython, you'll need to first reinstall CircuitPython firmware for your board. The QSPI flash should have retained its contents. If you don't see anything on the CIRCUITPY volume, copy files from the backup you made earlier to CIRCUITPY.

To verify the new ESP32 WiFi firmware version is correct, follow the Connect to WiFi step in this guide and come back here when you've successfully run the code. The REPL output should display the firmware version you flashed.

(Advanced) Upload NINA Firmware with ESPTool.py

For advanced users who have esptool.py installed, run the following commands on your command line:

If you're using macOS or Linux - run the following command, replacing /dev/ttyACM0 with the serial port of your board and NINA_W102-1.6.0 with the binary file you're flashing to the ESP32.

esptool.py --port /dev/ttyACM0 --before no_reset --baud 115200 write_flash 0 NINA_W102-1.6.0.bin

If you're using Windows - run the following command, replacing COM7 with the serial port of your board  and NINA_W102-1.6.0 with the binary file you're flashing to the ESP32

esptool.py --port COM7 --before no_reset --baud 115200 write_flash 0 NINA_W102-1.6.0.bin

The command should detect the ESP32 and will take a minute or two to upload the firmware. 

• If ESPTool doesn't detect the ESP32, make sure you've uploaded the correct .UF2 file to the bootloader and are using the correct serial port.

Once the firmware is fully uploaded, press the Reset button (or, on the RP2040 Pico, unplug your device from USB power) to get out of the ROM bootloader mode.