pyOCD is an Open Source python 2.7 based library for programming and debugging ARM Cortex-M microcontrollers using CMSIS-DAP. Linux, OSX and Windows are supported.
You can use the following interfaces:
- From a python interpretor:
- halt, step, resume execution
- read/write memory
- read/write block memory
- read-write core register
- set/remove hardware breakpoints
- flash new binary
- reset
- From a GDB client, you have all the features provided by gdb:
- load a .elf file
- read/write memory
- read/write core register
- set/remove hardware breakpoints
- high level stepping
- ...
The latest stable version of pyOCD may be done via pip as follows:
$ pip install --pre -U pyocd
To install the latest development version (master branch), you can do the following:
$ pip install --pre -U https://github.com/mbedmicro/pyOCD/archive/master.zip
Note that you may run into permissions issues running these commands. You have a few options here:
- Run with
sudo -H
to install pyOCD and dependencies globally - Specify the
--user
option to install local to your user - Run the command in a virtualenv local to a specific project working set.
If you encounter issue where pyocd-tool list
won't detect attached boards without sudo, the reason could be in access permissions. In Ubuntu 16.04 these are handled with udev and can be solved by adding a new udev rule.
Example udev rule for NXP FRDM-K64F:
- Create or append file
/etc/udev/rules.d/50-mbed.rules
with the following contents:
# 0d28:0204 NXP FRDM-K64F SUBSYSTEM=="usb", ATTR{idVendor}=="0d28", ATTR{idProduct}=="0204", MODE:="666"
- If you use different board, you can check the IDs with
dmesg
command.- Run
dmesg
- Plug in your board
- Run
dmesg
again and check what was added - Look for line similar to
usb 2-2.1: New USB device found, idVendor=0d28, idProduct=0204
- Run
You can also install from source by cloning the git repository and running
python setup.py install
When you install pyOCD via pip, you should be able to execute the following in order to start a GDB server powered by pyOCD:
pyocd-gdbserver
You can get additional help by running pyocd-gdbserver --help
.
The GDB server works well with Eclipse and the GNU ARM Eclipse OpenOCD plug-in. To view register the Embedded System Register Viewer plugin can be used. These can be installed from inside eclipse using the following links: GNU ARM Eclipse: http://gnuarmeclipse.sourceforge.net/updates Embedded System Register Viewer: http://embsysregview.sourceforge.net/update
The pyOCD gdb server executable will run as a drop in place replacement for
OpenOCD. If a supported mbed development board is being debugged the target
does not need to be specified, as pyOCD will automatically determine this.
If an external processor is being debugged then -t [processor]
must
be added to the command line. For more information on setup see
this post for OpenOCD
PyOCD developers are recommended to setup a working environment using virtualenv. After cloning the code, you can setup a virtualenv and install the PyOCD dependencies for the current platform by doing the following:
$ virtualenv env
$ source env/bin/activate
$ pip install -r dev-requirements.txt
On Windows, the virtualenv would be activated by executing
env\Scripts\activate
.
To run the unittests, you can execute the following. Because of how nose searches for tests, specifying the directory is important as it will otherwise attempt to run non-unit tests as well (which will hang).
$ nosetests pyOCD/tests
To get code coverage results, do the following:
$ nosetests --with-coverage --cover-html --cover-package=pyOCD pyOCD/tests
$ firefox cover/index.html
A series of tests are provided in the test directory:
- basic_test.py: a simple test that checks:
- read/write core registers
- read/write memory
- stop/resume/step the execution
- reset the target
- erase pages
- flash a binary
- gdb_test.py: launch a gdbserver
- gdb_server.py: an enhanced version of gdbserver which provides the following options:
- "-p", "--port", help = "Write the port number that GDB server will open."
- "-b", "--board", help="Connect to board by board id."
- "-l", "--list", help = "List all connected boards."
- "-d", "--debug", help = "Set the level of system logging output."
- "-t", "--target", help = "Override target to debug."
- "-n", "--nobreak", help = "Disable halt at hardfault handler."
- "-r", "--reset-break", help = "Halt the target when reset."
- "-s", "--step-int", help = "Allow single stepping to step into interrupts."
- "-f", "--frequency", help = "Set the SWD clock frequency in Hz."
- "-o", "--persist", help = "Keep GDB server running even after remote has detached."
- "-bh", "--soft-bkpt-as-hard", help = "Replace software breakpoints with hardware breakpoints."
- "-ce", "--chip_erase", help="Use chip erase when programming."
- "-se", "--sector_erase", help="Use sector erase when programming."
- "-hp", "--hide_progress", help = "Don't display programming progress."
- "-fp", "--fast_program", help = "Use only the CRC of each page to determine if it already has the same data."
from pyOCD.board import MbedBoard
import logging
logging.basicConfig(level=logging.INFO)
board = MbedBoard.chooseBoard()
target = board.target
flash = board.flash
target.resume()
target.halt()
print("pc: 0x%X" % target.readCoreRegister("pc"))
# pc: 0xA64
target.step()
print("pc: 0x%X" % target.readCoreRegister("pc"))
# pc: 0xA30
target.step()
print("pc: 0x%X" % target.readCoreRegister("pc"))
# pc: 0xA32
flash.flashBinary("binaries/l1_lpc1768.bin")
print("pc: 0x%X" % target.readCoreRegister("pc"))
# pc: 0x10000000
target.reset()
target.halt()
print("pc: 0x%X" % target.readCoreRegister("pc"))
# pc: 0xAAC
board.uninit()
Python:
from pyOCD.gdbserver import GDBServer
from pyOCD.board import MbedBoard
import logging
logging.basicConfig(level=logging.INFO)
board = MbedBoard.chooseBoard()
# start gdbserver
gdb = GDBServer(board, 3333)
gdb server:
arm-none-eabi-gdb basic.elf <gdb> target remote localhost:3333 <gdb> load <gdb> continue
A target defines basic functionalities such as step
, resume
, halt
,
readMemory
, etc. You can inherit from Target to implement your own methods.
Then declare your target in TARGET (in pyOCD.target.__init__.py
)
Defines the transport used to communicate. In particular, you can find CMSIS-DAP.
Implements methods such as memWriteAP
, memReadAP
, writeDP
, readDP
, ...
You can inherit from Transport
and implement your own methods.
Then declare your transport in TRANSPORT
(in pyOCD.transport.__init__.py
)
Contains flash algorithm in order to flash a new binary into the target.
Start a GDB server. The server listens on a specific port. You can then connect a GDB client to it and debug/program the target.
Then you can debug a board which is composed by an interface, a target, a transport and a flash