CW303 XMEGA Target

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:

The following shows several of the connectors available on the CW301.

20-Pin Connector

J2 is a 20-pin connector, which uses the standard NewAE 20-pin connector pinout. See the ChipWhisperer-Lite documentation for details.

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.

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.

The XMEGA uses AVR architecture and needs an AVR compiler. The target firmware can be found under the chipwhisperer/hardware/victims/firmware/ 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:

1. cd to the project directory with the firmware source (.c) and makefile, and run make:

   cd c:\chipwhisperer\hardware\victims\firmware\<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.

2. 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.

Sets up the ability for communication with the target using the ChipWhisperer scope.

import chipwhisperer as cw

scope = cw.scope()
target = cw.target(scope)

scope.gain.gain = 45
scope.adc.samples = 25000
scope.adc.offset = 0
scope.adc.basic_mode = "rising_edge"
scope.clock.clkgen_freq = 7370000
scope.clock.adc_src = "clkgen_x4"
scope.trigger.triggers = "tio4"
scope.io.tio1 = "serial_rx"
scope.io.tio2 = "serial_tx"
scope.io.hs2 = "clkgen"

To program the device you need to have completed the Communication, and the Compiling sections. The firmware source files can be found in their directories under the chipwhisperer/hardware/victims/firmware/ directory.

from chipwhisperer.capture.api.programmers import XMEGAProgrammer

programmer = XMEGAProgrammer()
programmer.scope = scope
programmer._logging = None
programmer.find()
programmer.erase()
programmer.program("<path to xmega firmware .hex file>", memtype="flash", verify=True)
programmer.close()