The libopencm3 project aims to create an open-source firmware library for
various ARM Cortex-M3 microcontrollers.

Currently (at least partly) supported microcontrollers:

 - ST STM32F1 series
 - ST STM32F2 series
 - ST STM32F4 series
 - NXP LPC1311/13/42/43

The library is written completely from scratch based on the vendor datasheets,
programming manuals, and application notes. The code is meant to be used
with a GCC toolchain for ARM (arm-elf or arm-none-eabi), flashing of the
code to a microcontroller can be done using the OpenOCD ARM JTAG software.

Status and API

The libopencm3 project is currently work in progress. Not all subsystems
of the microcontrollers are supported, yet.

IMPORTANT: The API of the library is NOT yet considered stable! Please do
           not rely on it, yet! Changes to function names, macro names etc.
           can happen at any time without prior notice!


 $ make

You may want to override the toolchain (e.g., arm-elf or arm-none-eabi):

 $ PREFIX=arm-none-eabi make

For a more verbose build you can use

 $ make V=1

Example projects

The library ships with a few small example projects which illustrate how
individual subsystems of the microcontrollers can be configured and used with

For flashing the 'miniblink' example (after you built libopencm3 and the
examples by typing 'make' at the top-level directory) onto the Olimex
STM32-H103 eval board (ST STM32F1 series microcontroller), you can execute:

 $ cd examples/stm32/f1/stm32-h103/miniblink
 $ make flash

The Makefiles of the examples are configured to use a certain OpenOCD
flash programmer, you might need to change some of the variables in the
Makefile if you use a different one.

You can also flash manually like this:

 $ openocd -f interface/jtagkey-tiny.cfg -f target/stm32f1x.cfg
 $ telnet localhost 4444
 > reset halt
 > flash write_image erase foobar.hex
 > reset

Replace the "jtagkey-tiny.cfg" with whatever JTAG device you are using, and/or
replace "stm32f1x.cfg" with your respective config file. Replace "foobar.hex"
with the file name of the image you want to flash.


 $ make install

This will install the library in /usr/local. If you want to install it
elsewhere, use the following syntax:

 $ DESTDIR=/opt make install

The recommended location is to install into your toolchain directory, e.g.
/home/someuser/sat for a toolchain built using the summon-arm-toolchain
script from https://github.com/esden/summon-arm-toolchain.

 $ DESTDIR=~/sat make install

Coding style and development guidelines



The libopencm3 code is released under the terms of the GNU Lesser General
Public License (LGPL), version 3 or later.

See COPYING.GPL3 and COPYING.LGPL3 for details.

Mailing lists

 * Developer mailing list (for patches and discussions):

 * Commits mailing list (receives one mail per 'git push'):