Flashing Guide - GC Ultimate Kickstarter Edition

USB Flashing Mode

Plug in the main PCB to a Desktop PC.

  1. Press and hold SW15 located on the rear side of the PCB.

  2. Press and release the reset button.

  3. Look for the RPI-RP2 USB drive to show up in your File Explorer/Finder under devices.

Download and Flash

Click this link to download the latest firmware file.

Ensure that you copy the correct file.

Copy the gcu_r4k.uf2 firmware file to the RPI-RP2 flash drive.

Your PCB will reboot automatically.

Baseband Update

The wireless firmware will require an update to work correctly.

Open our configuration app page using a compatible web browser (Chrome, Edge, Brave): https://handheldlegend.github.io/hoja2/

Connect your GCU board:

Click Connect…

Click on the device name, then click ‘Connect’ again.

Click on the ‘Wireless’ configuration option

Click ‘Enter Baseband Mode’ to reboot the board into the baseband update mode.

At this stage, there should be an LED flashing orange on the board to indicate success for entering the proper update mode.

Navigate to our Baseband Update Tool

Click ‘Connect’

Click the device name, then click Connect once more.

You should see ‘Stub running’ in the terminal which will indicate that the device has successfully connected to the update tool, and is ready to proceed.

Connection Troubleshooting

If you are using an AMD System or you are having issues connecting…

See our comprehensive baseband flashing troubleshooting guide which is a solution for most customers to get you fully flashed.

One specific step for the GC Ultimate you may try to assist with connecting is to press and hold the SW16 switch on the front of the PCB while you click ‘Enter Baseband Mode’.

Keep the button held until the connection succeeds.

Erase and Flash Baseband

Click Erase and wait for the operation to complete.

Finally, click Flash and wait for that process to complete.

You’ll see progress as shown. Wait until the process reaches 100%.

You may now unplug your main board.

You’re fully updated now, and you may proceed to our Build Guide