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CW1173 ChipWhisperer-Lite/Upgrading SAM3U Firmware

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This section has been recently updated for ChipWhisperer 5. The previous version can be found here:

When talking about the ChipWhisperer's firmware, there is really two parts to this:

  1. The FPGA Bitstream file.
  2. The SAM3U USB interface chip firmware.

The FPGA bitstream alone is what is normally configured by the ChipWhisperer-Capture software. This bitstream is always the most up-to-date, since it's automatically reloaded by the computer every time you power cycle the ChipWhisperer-Capture. The SAM3U firmware however is not automatically updated, but it tends to change less frequently.

Checking Firmware Version

The firmware version is printed at start-up. You will see a line that looks like this indicating the version of the SAM3U Firmware:

Found CW-Lite, Serial Number = 442031204630xxxxxxxxxxx
SAM3U Firmware version = 0.11 b0
Programmed FPGA

If your firmware version is outdated, a warning will be printed. You can also see the firmware version in the Config CW Firmware dialog:


Note the main version is 0.11 in this example. The "b0" indicates a "build" number. Typically this will be "build 0", but special versions will use a different build number to indicate a variant of a regular version.

Upgrading Firmware

See for instructions on how to update the SAM3U firmware.

Linux usbserial module Workaround

There is an issue in some versions of Linux, where the SAM3U is not assigned a serial port when it enters bootloader mode. Here are some steps to resolve this issue (Note. this is not a permanent fix, you must go through these steps each time you put your ChipWhisperer into bootloader mode.). These steps assume you've already put ChipWhisperer into bootloader mode.

  1. Unplug your ChipWhisperer (Leave unplugged until instructed otherwise)
  2. Reboot your computer
  3. Once logged in again, open a terminal session
  4. Run this command: sudo modprobe usbserial vendor=0x3eb product=0x6124
  5. Plug your ChipWhisperer back in
  6. Check that a serial port is now open using: ls -l /dev/ttyUSB*

TtyUSB example.png

You should now be able to program the bootloader from ChipWhisperer Capture through the port you created

Manual Update

If the above instructions fail, there is no big problem. The SAM3U chip contains a hardware-resident bootloader. You may need to follow instructions on the Manual SAM3U Firmware Update page (including using BOSSA) if you are unable to use the automatic system that is part of ChipWhisperer-Capture.