Coldcard Wallet

Coldcard is a Cheap, Ultra-secure & Opensource Hardware Wallet for Bitcoin. Get yours at ColdcardWallet.com

Follow @COLDCARDwallet on Twitter to keep up with the latest updates and security alerts.

Check-out and Setup

Do a checkout, recursively to get all the submodules:

git clone --recursive https://github.com/Coldcard/firmware.git

Then:

• cd firmware
• git submodule update --init (if needed?)
• brew install autogen
• virtualenv -p python3 ENV (Python > 3.5 is required)
• source ENV/bin/activate (or source ENV/bin/activate.csh based on shell preference)
• pip install -r requirements.txt

Setup and Run the Desktop-based Coldcard simulator:

• cd unix; make setup && make; ./simulator.py

Building the firmware:

• cd ../cli; pip install --editable .
• cd ../stm32; make setup && make; make firmware-signed.dfu
• The resulting file, firmware-signed.dfu can be loaded directly onto a Coldcard, using this command (already installed based on above)
• ckcc upgrade firmware-signed.dfu

Which looks like this:

[ENV] [firmware/stm32 42] ckcc upgrade firmware-signed.dfu
675328 bytes (start @ 293) to send from 'firmware-signed.dfu'
Uploading  [##########--------------------------]   29%  0d 00:01:04

MacOS

You'll probably need to install at least these packages:

brew cask install xquartz
brew install sdl2
brew cask install gcc-arm-none-eabi

Used to be these were needed as well:

brew install sdl2
brew tap PX4/px4
brew search px4
brew install px4/px4/gcc-arm-none-eabi-80 (latest gcc-arm-none-eabi-XX, currently 80)

You may need to reboot to avoid a DISPLAY is not set error.

Linux

You'll probably need to install these (Ubuntu 16):

apt install libudev-dev python-sdl2 gcc-arm-none-eabi

If you get stuck on the "Skip PIN" screen after the startup, edit the pyb.py file located under /unix/frozen-modules/ and follow the instructions from line 27 to line 31:

# If on linux, try commenting the following line
addr = bytes([len(fn)+2, socket.AF_UNIX] + list(fn))
# If on linux, try uncommenting the following two lines
#import struct
#addr = struct.pack('H108s', socket.AF_UNIX, fn)

Code Organization

Top-level dirs:

shared

• shared code between desktop test version and real-deal
• expected to be largely in python, and higher-level

unix

• unix (MacOS) version for testing/rapid dev
• this is a simulator for the product

testing

• test cases and associated data

stm32

• embedded micro version, for actual product
• final target is a binary file for loading onto hardware

external

• code from other projects, ie. the dreaded submodules

stm32/bootloader

• 32k of factory-set code that you cannot change
• however, you can inspect what code is on your coldcard and compare to this.

hardware

• schematic and bill of materials for the Coldcard