STM32F4 Template

This is a simple "stm32f4-template" example using the Standard Peripheral Library for STM32F4 Discovery board.

Files

Here is an overview of the files found in this project:

• .gdbinit: contains startup commands for gdb, the debugger. This file is a copy of the original by Ross Wolin.
• Makefile: commented makefile used to compile this project. You can use this file to see how the whole compilation process works and how to use the tools.
• main.c: this is the actual program (with comments).
• stm32_flash.ld: linker script provided by ST. Contains a description of the memory layout used by the Cortex-M4.
• stm32f4xx_conf.h: this file is used to include the header files of the standard peripheral library. It is a configuration file. You could include those headers directly in main.c, but the peripheral library includes this configuration header (stm32f4xx.h includes it conditionally), so we must provide it - or else we cannot compile our code against the library. This file is provided by ST and is supposed to be adapted to every project.
• system_stm32f4xx.c: implements intialization code called from the startup file startup_stm32f4xx.s (present in the library). This file is provided by ST.

Missing files

This project does not include the peripheral library used to build the program. You can however download the library from ST (see link below). In my setup I have extracted the library in a folder one level above the "stm32f4-template" folder.

Tools and software requirements

• GCC ARM Embedded toolchain for ARM Cortex-M. You need this in order to compile and debug your code. You can download pre-built binaries for all major operating systems. After downloading, just extract the archive somewhere (a good place: /opt/gcc-arm-embedded/), no installation is required. The exact location of the extracted folder will be used in the makefile.

• stlink utility written by texane. You need this for flashing the compiled code to the board. It also contains a gdb server used to debug your code on the chip. Install this from the source code or if you are on OS X, you can do it from brew: brew install stlink

• The STM32F4DISCOVERY board firmware package. You need this library in order to access and use the board's peripherals. It contains headers and source files which you compile and link together with your own files.

• make. You need this in order to... make this project. make should be pre-installed on all Linux and OS X machines.

Usage

1. Download and install the requirements mentioned above.
2. Download or clone this repository.
3. Edit the Makefile if needed.
4. Open a terminal window and change to the stm32f4-template directory.
5. Type make.
6. Connect the stm32f4 discovery board to your computer.
7. If you just want to flash the stm32f4-template program, type make flash.
8. If you want to debug the program:
   1. Start the gdb server included in the stlink package by typing st-util. You should start st-util in a separated terminal window so that it does not polute the gdb session.
   2. Type make debug. This will start gdb which will read the .gdbinit file and thus connect to localhost port 4242, where st-util is listening. From this point on, st-util will take commands from gdb and control the discovery board.
   3. In the gdb window, type break main to set up a break point to the main function.
   4. Type continue.
   5. Have fun.

Thanks

• Many thanks to texane for writting the stlink utility!