Uploading bitstream to CW312T-A35 using Husky

Embedded Security ChipWhisperer Software
1

This is a related/follow up question to Uploading Bitstream to CW312T-A35 through CW HUSKY and CW313 Target support - Embedded Security / ChipWhisperer Hardware - NewAE Forum

I’ve been having a lot of trouble glitching AES encryption on the CW312T-A35 Husky target, and I’ve determined a possible issue could be that the bitstream may not be properly uploaded. After doing these steps:

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

scope.io.hs2 = 'clkgen'
platform = 'ss2_a35'

from chipwhisperer.hardware.naeusb.programmer_targetfpga import CW312T_XC7A35T
fpga = CW312T_XC7A35T(scope)

# Set to None during programming for better programming reliability (See https://github.com/newaetech/chipwhisperer/blob/develop/software/chipwhisperer/hardware/naeusb/programmer_targetfpga.py)
scope.io.hs2 = None
fpga.program('ss2_aes_wrapper.bit', sck_speed=10e6)
scope.io.hs2 = 'clkgen'

# CW312 is a subset of 305, so use the 305 target
target = cw.target(scope, cw.targets.CW305, force=False, fpga_id=None, platform=platform, program=False)

and checking if the bitstream was uploaded (I got this from the same post):

status = fpga.done_state()
if status:
    print("✅ FPGA programmed.")
else:
    print("❌ FPGA Not Programmed.")

status evaluates to True. However, running target.is_programmed() returns False.

My question(s) is/are: is fpga.done_state() a reliable way to tell if the bitstream is uploaded? Why is target.is_programmed() returning False? Am I missing something that is preventing ss2_aes_wrapper.bit from being properly uploaded? Thanks in advance for your help.

2

Yes, done_state() is reliable (it reflects the state of the FPGA’s DONE_0 pin).
is_programmed() is only valid on the CW305- sorry for the confusion here, I’ll update the API to make that clear.

I’m not seeing anything wrong in your code. Does the target reliably respond to a register read after programming?

3

Okay, thank you. I suppose that isn’t where my problem lies then.

Yes, register reads respond as expected.