Release 4.0.1

Compatible with desktop app versions v4.0.1 or newer.

Release notes:

• Remove previously deprecated USB API backup recovery
• More efficient and robust EEPROM storage
• On system faults, clear memory and disable SPI and I2C peripherals

To reproduce and verify the deterministic build:

# Clone the repository
git clone https://github.com/digitalbitbox/mcu.git
cd mcu

# Build deterministically (requires Vagrant and Virtualbox and OSX or Linux)
vagrant up
cp build-vagrant/bin/firmware.pad.bin firmware.deterministic.4.0.1.bin
vagrant halt

# Verify the deterministic binary
shasum -a 256 firmware.deterministic.4.0.1.bin  #  b9b8ef141d71c537a03371aa888147669ff0405954b282ed24cc413eb164db08

# Append signatures of the firmware
py/prepend_signatures_firmware_binary.py firmware.deterministic.4.0.1.bin firmware.deterministic.4.0.1.signed.bin 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

# Verify the signed deterministic binary
shasum -a 256 firmware.deterministic.4.0.1.signed.bin  #  ae2ff91e917dd70b02bbdb025fc6eaa056bb55aa2f2802cf6fa02f3261d37234

# Signed deterministic binaries can be loaded into the Digital Bitbox 
# using the Upgrade Firmware button in the desktop app.

# In case of problems, check if using a different major version:
vagrant --version  #  Vagrant 1.8.5
vagrant box list   #  ubuntu/trusty64 (virtualbox, 20181103.0.0)
virtualbox --help  #  Oracle VM VirtualBox Manager 5.1.38

ECC secp256k1 public keys and signatures of the double SHA256 hash of firmware.deterministic.4.0.1.bin:

0263b742d9873405c609814da884324ab0f4c1597a5fd152b388899857f4d041df : f89c9481d32e49e3dd3770d881d711e048964657e1532efba759fbfd067ef60f39568e8411766d47932d87da2c9ce33e53eabcc4b1ddd230506658084ba5544a
02b95dc22d293376222ef896f74a8436a8b6672e7e416299f3c4e23b49c38ad366 : 0416cf3aad238a30d94ce4884ac9e3e350f807402f6b6dd204e8ba5a8cad5d0179e6c7f1503d665c3be41dcc437eb68dd0d956f11f5c6d5ff4d45892b0f7179a
03ef4c48dc308ace971c025db3edd4bc5d5110e28e14bdd925fffafd4d21002800 : fb22728ed783fef1cac48e5ebd1160a503baec0076adf963088717d48ba0d31a7f01445382196f66b71ee08e2c504a4e7d7a7972464aa3c27eb61668303ff643
030d8b0b86fca70bfd3a8d842cdb3ff8362c02f455fd092b080f1bb137dfc1d25f : 2d4983c0628424a63f9aa37acaf1faedb1b3ca69dd176161115ba6caf18b96c417322c4509325ff2d0945bcb95233db8da35804eb4f80fbfa20588d85b205794

Signature blob appended to firmware.deterministic.4.0.1.bin

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