CW303 XMEGA Target

CW303 XMEGA Target#

The ChipWhisperer-Lite board has a break-away target board section. This target can be used attached to the CW-Lite or separated and connected via ribbon cable. The breakaway target board has a slightly different feature set than the CW308T-XMEGA target board.

Specifications#

Feature	Notes/Range
Target Device	ATXmega128D4-AU
Target Architecture	8-bit Harvard
Vcc	3.3V
Programming	PDI
Hardware Crypto	No
Availability	ChipWhisperer-Lite 1-part/2-part
Status	Released
Shunt	49.9Ω

Available with the ChipWhisperer-Lite Starter Kit

LEDs#

The two LEDs on the XMEGA board are active-low, which is done to reduce the impact on power consumption in the VCC power signature. The connections are as follows:

Item	Connection	Note
LED9	PORTA.5	Active low
LED10	PORTA.6	Active low

Usage#

Building Firmware#

Building firmware for this target requires make and avr-gcc. Installation of both these are covered in the installation instructions.

If you have make and avr-gcc, you can build firmware by navigating via command line to the relevant build directory and running:

make PLATFORM=CWLITEXMEGA CRYPTO_TARGET=<CRYPTO_TARGET>

Typically CRYPTO_TARGET here is TINYAES128C, AVRCRYPTOLIB or NONE.

If you’re running a Jupyter Notebook lab, typically this step will be contained within one of the code blocks.

Programming Firmware#

The ChipWhisperer-Lite and ChipWhisperer-Pro have integrated PDI programmers, meaning there’s no need to use an external one if you’re using either. To program via the ChipWhisperer API:

# ...assuming scope is setup
# ensure device has clock and IO is setup, typically via scope.default_setup()
prog = cw.programmers.XMEGAProgrammer
cw.program_target(scope, prog, "<path/to/firmware.hex>")

Connectors#

The following shows several of the connectors available on the CW303.

20-Pin Connector#

J2 is a 20-pin connector, which uses the standard NewAE 20-pin connector pinout, documented here.

SMA Glitch#

The SMA glitch connector allows VCC glitches be inserted into the VCC pin. This is done by shorting the resistive shunt R66. By default it connects to the SMA measure connector, but can be disconnected with the solder jumpers.

SMA Measure#

The SMA measure connector allows power measurements to be taken across resistive shunt R66. By default it connects to the SMA glitch connector, but can be disconnected with the solder jumpers.

JP13#

JP13 provides a pinout with several extra pins from the XMEGA device.

Solder Jumpers#

SJ2#

Selects the source of the input to the VCC filter - either the 20-pin 3.3V VCC (default), or the optional voltage regulator which derives the power from a USB-Micro connector.

SJ3#

Connects the output of the VCC filter to the XMEGA VCC network. Soldered by default.

SJ4#

Connects the SMA Measure header to the resistive shunt. Soldered by default.

SJ5#

Connects the SMA Glitch header to the resistive shunt. Soldered by default.

SJ7#

Connects the VCC of the XMEGA board to VREF on 20-pin header. Soldered by default.

Mounting Jumpers#

Note the ChipWhisperer-Lite main board and target section contain a number of jumper options. By default these are not mounted, and solder jumper bridges on the PCB have been bridged to select the appropriate options when required. Some options are only solder jumpers, which to move the jumper requires a soldering iron to bridge or clear the appropriate connections.

The following lists jumpers on the ChipWhisperer-Lite / Target Section:

JP7 connects the “MEASURE” SMA to the XMEGA VCC Rail. Shorted by default with SJ4
JP6 connects the “GLITCH” SMA to the XMEGA VCC rail. Shorted by default with SJ5
JP12 can be used to feed an external voltage into the XMEGA VCC rail. By default SJ3 connects this to 3.3V
SJ2 selects if the 3.3V rail comes from the 20-pin IDC connector (i.e. ChipWhisperer-Lite board) or via an optional LDO and USB connector

Building firmware#

The XMEGA uses AVR architecture and needs an AVR compiler (which you’ll have if you followed our Installation instructions).

The target firmware can be found under the chipwhisperer/firmware/mcu/ directory in their project (e.g. simpleserial-aes, basic-passwdcheck) folder.

Atmel AVR-GCC standalone - see Atmel avr-gcc standalone (registration required)
WinAVR. Last release - 2010, see WinAVR Page (no registration required)

To build the code, follow these steps:

cd to the project directory with the firmware source (.c) and makefile, and run make: cd c:\chipwhisperer\firmware\mcu<project dir> make PLATFORM=CW303 CRYPTO_TARGET=AVRCRYPTOLIB where the <> part is changed to the project name. If this is successful, you’ll see an output like the following:

If instead you get an error something like make: *** No rule to make target `simpleserial.elf', needed by `elf'. Stop., this means a required file was missing.
The compiled firmware file you will use to program the target will have the format <sourcefile name>-CW303.hex, where the <> part will change based on the project.