Developer notes for Specter-DIY

Compiling the code yourself

See the build documentation for instructions on how to compile the code.

Enabling developer mode

By default USB communication is off. This means that when you connect the board to the computer it will NOT mount the PYBFLASH anymore and there will be no way to connect to debug shell.

In order to connect to the board, modify those lines in boot.py like this:

# configure usb from start if you want, 
# otherwise will be configured after PIN
pyb.usb_mode("VCP+MSC") # debug mode with USB and mounted storages from start
#pyb.usb_mode("VCP") # debug mode with USB from start
# disable at start
# pyb.usb_mode(None)
# os.dupterm(None,0)
# os.dupterm(None,1)

and after flashing, restart the device, go to Device settings > Communication > USB communication, turn it on and Confirm. Then you can connect using the micro-USB port and with something like:

# Linux
screen /dev/ttyACM0 115200 # or maybe ttyACM1 or ttyACM2
# Mac
screen /dev/tty.usbmodem14403 115200

All print() statements will appear in the terminal output. You can keep both the mini-USB and micro-USB connected at the same time, with the power jumper in either position. This makes it easier to flash the firmware and then connect to the device.

Writing a simple app

Specter can be extended with custom apps. Most of the functionality is already splitted into apps, like WalletManager to manage your wallets, MessageApp to sign bitcoin messages, XpubApp to show master public keys etc.

Check out the apps folder to understand how they work.

TODO: More detailed description