pycs

Python Based ARM CoreSight Debug and Trace Tools

deadsy
45
9
Python

pycs

Python Based ARM CoreSight Debug and Trace Tools

  • PyCS is a python based JTAG/SWD debugger for ARM chips.
  • Its current focus is systems using Cortex-M ARM CPUs.
  • It reads the SoC SVD files to give full peripheral/register decodes for a wide variety of Cortex-M based chips.

What do I need?

Installing the tool

  • Run “make” - this will build the ARM disassembler library.
  • Run “./pycs” in the same directory you extracted the code to.
  • If you don’t have permissions to access USB devices you can fix that (with a udev rules file) or run with “sudo ./pycs”

Current Targets

$ ./pycs -l
supported targets:
  axoloti       : Axoloti Synth Board (STM32F427xG)
  efm32lg       : EFM32 Leopard Gecko Starter Kit (EFM32LG990F256)
  frdm_k64f     : FRDM-K64F Kinetis Development Board (MK64FN1M0VLL12)
  mb1035b       : STM32F3 Discovery Board (STM32F303xC)
  mb1075b       : STM32F4 Discovery Board (STM32F429xI)
  mb997c        : STM32F4 Discovery Board (STM32F407xx)
  nRF51822      : Adafruit BLE USB dongle (nRF51822)
  nRF52dk       : Nordic nRF52DK Development Board (nRF52832)
  nucleo-l432kc : Nucleo-L432KC (STM32L432KC)
  saml21        : Atmel SAM L21 Xplained Pro Evaluation Board (ATSAML21J18B)
  tepo          : Teenage Engineering Pocket Operator (EFM32LG890F128)

Dependencies

  • sudo apt-get install python3-lxml
  • sudo apt-get install python3-hid

Using the Tool

$ ./pycs -t mb997c

pycs: ARM CoreSight Tool 1.0
STM32F407xx: compiling ./vendor/st/svd/STM32F40x.svd.gz
ST-Link usb 0483:3748 serial u"H\xffj\x06PuIU'3\x04\x87"
target voltage 2.889V

mb997c*>

It has an interactive CLI.

  • ‘?’ for menu help
  • ‘?’ for command completion/argument help
  • TAB for command completion
  • ‘help’ for general help

Features

  • display memory
  • disassemble memory
  • display system control registers
  • display peripheral registers
  • halt/go the cpu
  • program flash
  • Segger RTT client
  • measure counter frequencies
  • etc. etc.

Other Documents