This repository contains assorted example projects for libopencm3.
The libopencm3 project aims to create an open-source firmware library for various ARM Cortex-M microcontrollers.
For more information visit http://libopencm3.org
The examples are meant as starting points for different subsystems on multitude of platforms.
Feel free to add new examples and send them to us either via the mailinglist or preferably via a github pull request.
You must run "make" in the top level directory first. This builds the library and all examples. If you're simply hacking on a single example after that, you can type "make clean; make" in any of the individual project directories later.
For more verbose output, to see compiler command lines, use "make V=1" For insanity levels of verboseness, use "make V=99"
The makefiles are generally useable for your own projects with only minimal changes for the libopencm3 install path (See Reuse)
Make Flash Target
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.
The make flash target also supports a few other programmers. If you provide the Black Magic Probe serial port the target will automatically choose to program via Black Magic Probe. For example on linux you would do the following:
cd examples/stm32/f1/stm32-h103/miniblink make flash BMP_PORT=/dev/ttyACM0
This will also work with discovery boards that got the st-link firmware replaced with the Black Magic Probe firmware.
In case you did not replace the firmware you can program using the st-flash program by invoking the stlink-flash target:
cd examples/stm32/f1/stm32vl-discovery/miniblink make miniblink.stlink-flash
If you rather use GDB to connect to the st-util you can provide the STLINK_PORT to the flash target.
cd examples/stm32/f1/stm32vl-discovery/miniblink make flash STLINK_PORT=:4242
You can also flash manually. Using a miriad of different tools depending on your setup. Here are a few examples.
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.
Black Magic Probe
cd examples/stm32/f1/stm32vl-discovery/miniblink arm-none-eabi-gdb miniblink.elf target extended_remote /dev/ttyACM0 monitor swdp_scan attach 1 load run
To exit the gdb session type
<Ctrl>-D. It is useful to add the
following to the .gdbinit to make the flashing and debugging easier:
set target-async on set confirm off set mem inaccessible-by-default off #set debug remote 1 tar ext /dev/ttyACM0 mon version mon swdp_scan att 1
Having this in your .gdbinit boils down the flashing/debugging process to:
cd examples/stm32/f1/stm32vl-discovery/miniblink arm-none-eabi-gdb miniblink.elf load run
This example uses the st-util by texane that you can find on GitHub.
cd examples/stm32/f1/stm32vl-discovery/miniblink arm-none-eabi-gdb miniblink.elf tar extended-remote :4242 load run
If you want to use libopencm3 in your own project, this examples repository shows the general way. (If there's interest, we can make a stub template repository)
Create an empty repository
mkdir mycoolrobot && cd mycoolrobot && git init .
Add libopencm3 as a submodule
git submodule add https://github.com/libopencm3/libopencm3
Grab a copy of the basic rules These urls grab the latest from the libopencm3-examples repository
wget \ https://raw.githubusercontent.com/libopencm3/libopencm3-examples/master/examples/rules.mk \ -O libopencm3.rules.mk
Grab a copy of your target Makefile in this case, for STM32L1
Edit paths in
Edit the last line of
libopencm3.target.mkand change the include to read include
../libopencm3.rules.mk(the amount of .. depends on where you put your project in the next step..
beg/borrow/steal an example project For sanity's sake, use the same target as the makefile you grabbed up above)
cp -a \ somewhere/libopencm3-examples/examples/stm32/l1/stm32ldiscovery/miniblink \ myproject
Add the path to OPENCM3_DIR, and modify the path to makefile include
diff -u --- 2014-01-24 21:10:52.687477831 +0000 +++ Makefile 2014-03-23 12:27:57.696088076 +0000 @@ -19,7 +19,8 @@ BINARY = miniblink +OPENCM3_DIR=../libopencm3 LDSCRIPT = $(OPENCM3_DIR)/lib/stm32/l1/stm32l15xxb.ld -include ../../Makefile.include +include ../libopencm3.target.mk
You're done :)
You need to run "make" inside the libopencm3 directory once to build the library, then you can just run make/make clean in your project directory as often as you like.