CW312T-RP2350

CW312T-RP2350#

This board supports the Raspberry Pi RP2350 microcontroller. It especially lets you experiment with features such as power analysis or fault injection, including testing the glitch detectors.

Specifications#

Feature

Notes/Range

Target Device

RP2350

Target Architecture

Arm & RISC-V

Vcc

1.0V (on-board LDO)

Programming

Bootloader

Hardware Crypto

No

Availability

Standalone

Status

Released

Shunt

TBD

Power Supply#

The RP2350 has an internal regulator. This regulator is not used in the board, instead power for the core is supplied by an external LDO on the board.

Firmware#

Available at newaetech/cw_rp2350_fw.git. Make sure to clone the Pico SDK submodule as well.

Building firmware requires the following packages:

sudo apt update
sudo apt install cmake gcc-arm-none-eabi libnewlib-arm-none-eabi build-essential

To build, run the following from the firmware folder:

export PICO_SDK_PATH="../../pico-sdk"
mkdir -p build
cd build
cmake -DPICO_PLATFORM=rp2350-arm-s ..
cd simpleserial-aes
make

Ignore warnings about TinyUSB if you don’t require USB support.

Programming#

The USB bootloader can be used by enabling the 12 MHz clock source. To program, do the following:

  1. Run scope.default_setup()

  2. Set scope.clock.clkgen_freq = 12E6

  3. Set PDIC low and time.sleep(0.5)

  4. Set NRST low and time.sleep(0.5)

  5. Set NRST to high-z (scope.io.nrst = None) and time.sleep(0.5)

  6. Set PDIC to high-z

Following this, a removable drive should appear, after which your generated UF2 file can be copied over. Your RP2350 will reboot and run your firmware.

The drive can be found in Python via the following code, requiring the wmi package on Windows:

def get_windows_drive_letter(self):
    import wmi
    letter = None
    c = wmi.WMI()
    for drive in c.Win32_LogicalDisk():
        # uncomment to print info of all connected drives
        #print(str(drive))
        #print(str(drive.Caption) + str(drive.VolumeName) + str(drive.DriveType))
        if drive.VolumeName == "RP2350":
            letter = drive.Caption
    return letter

def linux_get_rpi_path(self):
    import subprocess
    result = subprocess.run(['blkid', '-l', '-o', 'device', '-t', 
                            'LABEL=RP2350', '-c', '/dev/null'],
                            capture_output=True)
    mnt = result.stdout.decode().strip()
    result = subprocess.run(['findmnt', mnt, '-no', 'TARGET'], capture_output=True)
    return result.stdout.decode().strip()

Troubleshooting#

Drive appears, then disappears before programming#

Try increasing the time.sleep() delays

Schematic#

The schematic is available here.

Board Layout#

See GIT Repo for gerber files.