Silicon Labs EFM8 Factory Bootloader client

This program talks with the factory pre-programmed AN945 USB bootloader on EFM8 devices.

Features

• .ihex firmware upload to EFM8UB1, EFM8UB2, EFM8UB3 chips
• device identification
• firmware dump!

Eventhough the AN945 protocol "doesn't allow" direct flash reading, it still allows checksumming via CRC16. That's enough to restore the complete flash image, albeit through a large-ish number of 07 Verify requests 8-)

Dependencies

• pyusb
• intelhex

That's it. Yes, we work over USB HID without any HID libraries. Cause they're all shit. See code.

Udev rules and permissions

Drop the included 70-efm8-bootloader.rules under /etc/udev/rules.d/, and sudo udevadm trigger.

Then the script can work without root. Depending on your distro, either udev's uaccess feature will grant that (not sure I understand how it works), or the classic plugdev group membership.

References

Application Note AN945: https://www.silabs.com/documents/public/application-notes/an945-efm8-factory-bootloader-user-guide.pdf