SCA101 (HARDWARE) course captures don't make sense with CW1173


I have a CWLITE with XMEGA target, I was able to complete all the setting up hardware tutorials and simple serial setup courses.

However, I have some questions regarding the first power analysis jupyter notebook course: SCA101.

TLDR: I run the captures, and graph the results, and I see this:

Doing 20 additions:

Doing a for loop with 20 iterations:

I am new to Power Analysis, so I don’t know if these readings make sense. However, what I see is that they are very different, compared to the samples included in the no-hardware versions of the course, which look like this when I graph them:

I am using the code included in the notebooks.

My questions:

  • Are the two first traces looking normal? Am I capturing power signals correctly?

  • What should the “IDLE” time of the CPU that the notebook mention look like? (See figure one, where the notebook says: “You shouldn’t see much happening here before the target starts idling”)

  • Why are my traces not visibly similar to the example ones?

  • What is the unit of the Y axis? Current?

Thank you

No, I’d say your ChipWhisperer isn’t hooked up correctly. Are you using a CWLite + CW308? If so, did you connect the measure port to J17 on the CW308?

The Y axis is a value proportional to current.


1 Like

I am using a ChipWhisperer-Lite Classic 8-bit ATXMEGA128D4 target (which according to the box is the cw1173). This one is directly connected to the target board and can program it (i.e.: I don’t have any SMA, my target is NOT the CW308, it’s the board that is on the same board as the CW itself, separated by a section that can be broken up to separate the two boards).

I’ve tested with the multimeter and the measure / glitch lines from the target board to the main board seem to be connected correctly.


I don’t believe that it’s necessary to connect any additional hardware, connector or cable, to measure the power consumption of the target, is that right?

Now I’m getting traces that look like this:

However, if I flash the simpleserial-base-lab2 firmware for the target again, and re-instantiate the scope, then I’m back at getting traces like the ones I show on the first post. What is going on? Could this be a hardware failure on my CW?

Yeah, your setup should be fine. Would you mind uploading a top-down picture of your Lite, so that I can do a visual inspection of the board? It could be that something got damaged during shipping.


Of course, here there are

Thank you a lot.

Thanks for uploading the photos. I don’t see anything jumping out at me, but I could be missing something. Out of curiosity, can you run the following and report the output:

import chipwhisperer as cw
import time
scope = cw.scope()

I just want to make sure it’s not a simple fix. Otherwise, we’re happy to either swap with a new unit, or take it back and repair it.


Hi Alex,

Here’s the output of that code:

cwlite Device
sn         = 442031204c5032433330393134323031
fw_version = 
    major = 0
    minor = 64
    debug = 0
gain = 
    mode = high
    gain = 30
    db   = 24.8359375
adc = 
    state          = False
    basic_mode     = rising_edge
    timeout        = 2
    offset         = 0
    presamples     = 0
    samples        = 5000
    decimate       = 1
    trig_count     = 16023690
    fifo_fill_mode = normal
clock = 
    adc_src       = clkgen_x4
    adc_phase     = 0
    adc_freq      = 29538459
    adc_rate      = 29538459.0
    adc_locked    = True
    freq_ctr      = 0
    freq_ctr_src  = extclk
    clkgen_src    = system
    extclk_freq   = 10000000
    clkgen_mul    = 2
    clkgen_div    = 26
    clkgen_freq   = 7384615.384615385
    clkgen_locked = True
trigger = 
    triggers = tio4
    module   = basic
io = 
    tio1         = serial_rx
    tio2         = serial_tx
    tio3         = high_z
    tio4         = high_z
    pdid         = high_z
    pdic         = high_z
    nrst         = high_z
    glitch_hp    = False
    glitch_lp    = False
    extclk_src   = hs1
    hs2          = clkgen
    target_pwr   = True
    tio_states   = (1, 1, 0, 0)
    cdc_settings = bytearray(b'\x00\x00\x00\x00')
glitch = 
    clk_src     = target
    width       = 10.15625
    width_fine  = 0
    offset      = 10.15625
    offset_fine = 0
    trigger_src = manual
    arm_timing  = after_scope
    ext_offset  = 0
    repeat      = 1
    output      = clock_xor

Thank you

Yeah, everything looks fine there. Can you send an email to so that we can get a new device delivered?