Error on calling `program_target` on CW305 with Cortex M3

On and off for the last week, I have been following the tutorial at I have now generated the .bit file and it seems to be working. I am using the CW305 as an FPGA target and the CW-Lite Part 2 for capture. Whenever I open the connection with the following script:

import chipwhisperer as cw

scope = cw.scope()

# program target:
bitstream = r"/home/gijsb/Documents/cw305-files/src/hardware/CW305_DesignStart/CW305_DesignStart.bit"
ftarget =, cw.targets.CW305, bsfile=bitstream, force=False)

# set clock:
# we only need PLL1:
ftarget.pll.pll_outenable_set(False, 0)
ftarget.pll.pll_outenable_set(True, 1)
ftarget.pll.pll_outenable_set(False, 2)

# run at 20 MHz:
ftarget.pll.pll_outfreq_set(20E6, 1)

# ensure ADC is locked:
assert (scope.clock.adc_locked), "ADC failed to lock"

scope.gain.gain = 60
scope.gain.mode = "high"
scope.adc.samples = 20000
scope.adc.offset = 0
scope.adc.basic_mode = "rising_edge"
scope.clock.clkgen_freq = 7370000
scope.clock.adc_src = "extclk_x4"
scope.trigger.triggers = "tio4" = "serial_rx" = "serial_tx" = "disabled"

import time

As long as the script continues to sleep, everything seems fine. The clock LED7 is blinking, if I press the SW4 to reset the LED5 blinks. However, when I try to program the target with the following script afterwards:

from chipwhisperer.capture.api.programmers import STM32FProgrammer
import os

program = STM32FProgrammer

aes_firmware_dir = os.path.dirname(os.path.realpath(__file__))
aes_hex_path = os.path.join(aes_firmware_dir, r"simpleserial-aes.hex")

print("Programming target...")
cw.program_target(scope, program, aes_hex_path, baud = 38400)
print("Programmed target")

It will return the error:

Programming Target...
Failed to detect chip. Check following:
   1. Connections and device power.
   2. Device has valid clock (or remove clock entirely for internal osc).
   3. On Rev -02 CW308T-STM32Fx boards, BOOT0 is routed to PDIC.
OSError: Could not detect STM32F, check connections, BOOT MODE entry setup

I am new to the whole FPGA thing, but I have done some ChipWhisperer on a CWLITE-ARM before. Is there something I am clearly doing wrong here? Maybe I am not supposed to use STM32FProgrammer? Perhaps my setup is incorrect? I have been searching for hours through the forum and documentation, but I cannot seem to find anything which hints at a solution or example. Does anyone have an idea?

Maybe for debugging purposes, here is my scope just before programming the target:

cwlite Device
sn         = 50203120324136503130313134323031
fw_version =
    major = 0
    minor = 30
    debug = 0
gain =
    mode = high
    gain = 60
    db   = 44.171875
adc =
    state          = False
    basic_mode     = rising_edge
    timeout        = 2
    offset         = 0
    presamples     = 0
    samples        = 20000
    decimate       = 1
    trig_count     = 335756915
    fifo_fill_mode = normal
clock =
    adc_src       = extclk_x4
    adc_phase     = 0
    adc_freq      = 117796142
    adc_rate      = 117796142.0
    adc_locked    = True
    freq_ctr      = 17111206
    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          = None
    target_pwr   = True
    tio_states   = (1, 1, 0, 0)
    cdc_settings = array('B', [1, 1])
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

At the top, you can see the setup I am using. And yes, I did plug in the devices when testing :slight_smile:

Thank you in advance,

Hi Gijs,
On the CW305 Arm DesignStart platform, the Arm firmware image is embedded in the FPGA bitfile, so you can’t program it with STM32FProgrammer as you would our “normal” STM32 targets.

If you follow the instructions here:,
look for the “Compile software” and “Update FPGA bitfile” sections. After these steps are followed, your CW305 FPGA bitfile contains the Arm firmware, and all you need to do is load the CW305 FPGA and you’re done.

Let me know if this still isn’t clear.

Hi Jean-Pierre,

Now I finally understand what the line “The Cortex target’s program memory is local to the FPGA, and the program memory contents is included in the FPGA bitfile” means. Stupid that I did not think of this immediately.

Thank you. I will try everything on Friday.

EDIT: For anyone in the future facing the same problem: This resolved the problem for me.