Installing the compiled code

With the secure bootloader initial installation of the firmware is slightly different. Upgrades are easier and don't require to connect hardware wallet to the computer.

Flashing initial firmware

Note If you don't want to use binaries from the releases check out the bootloader documentation that explains how to compile and configure it to use your public keys instead of ours.

  • If you are upgrading from versions below 1.4.0 or uploading the firmware for the first time, use the initial_firmware_<version>.bin from the releases page.
    • Verify the signature of the sha256.signed.txt file against Stepan's PGP key
    • Verify the hash of the initial_firmware_<version>.bin against the hash stored in the sha256.signed.txt
  • If you are upgrading from an empty bootloader or you see the bootloader error message that firmware is not valid, check out the next section - Flashing signed Specter firmware.
  • Make sure the power jumper of your discovery board is at STLK position
  • Connect the discovery board to your computer via the miniUSB cable on the top of the board.
    • The board should appear as a removable disk named DIS_F469NI.
  • Copy the initial_firmware_<version>.bin file into the root of the DIS_F469NI filesystem.
  • When the board is done flashing the firmware the board will reset itself and reboot to the bootloader. Bootloader will check the firmware and boot into the main firmware. If see an error message that no firmware is found - follow the update instructions and upload firmware via SD card.
  • Now you can switch the power jumper where you like it and power the board from the powerbank or battery.

Flashing signed Specter firmware

  • Download the specter_upgrade_<version>.bin from the releases.
  • Copy this binary to the root of the SD card (FAT-formatted)
    • Make sure only one specter_upgrade***.bin file is in the root directory
  • Insert SD card to the SD slot of the discovery board and power on the board
  • Bootloader will flash the firmware and will notify you when it's done.
  • Reboot the board - you will see Specter-DIY interface now, it will suggest you to select your PIN code

Upgrading firmware later on

Whenever a new release is out just download the specter_upgrade_<version>.bin from the releases, drop it to the SD card and upgrade the device just like in the previous step. Bootloader will make sure only signed firmware can be loaded to the board.

How to find out firmware version

Create an empty file on the SD card named .show_version and insert into the device. On every boot the bootloader will check if this file is present and if so - it will show information about current firmware and bootloader versions.