Open source version of the STMicroelectronics Stlink Tools

HOWTO

First, you have to know there are several boards supported by the software. Those boards use a chip to translate from USB to JTAG commands. The chip is called stlink and there are two versions:

STLINKv1, present on STM32VL discovery kits,
STLINKv2, present on STM32L discovery and later kits.

Two different transport layers are used:

STLINKv1 uses SCSI passthru commands over USB
STLINKv2 and STLINKv2-1 (seen on nucleo boards) uses raw USB commands.

Installation

Currently there are no binaries for Windows available (see issue #166). It is known to compile and work with MinGW(64)/Cygwin environment. Building with Visual Studio is not supported because the project uses POSIX APIs and probably will never change.

For Debian Linux based distributions there is no package available in the standard repositories so you need to install from source yourself.

Arch Linux users can install from the repository

FreeBSD users can install from freshports

Mac OS X users can install from homebrew

OpenBSD users need to install from source.

Installation from source (advanced users)

When there is no executable available for your platform or you need the latest (possible unstable) version you need to compile yourself. This is explained in the compiling manual.

Using the gdb server

To run the gdb server:

$ make && [sudo] ./st-util

There are a few options:

./st-util - usage:

  -h, --help		Print this help
  -vXX, --verbose=XX	Specify a specific verbosity level (0..99)
  -v, --verbose		Specify generally verbose logging
  -s X, --stlink_version=X
			Choose what version of stlink to use, (defaults to 2)
  -1, --stlinkv1	Force stlink version 1
  -p 4242, --listen_port=1234
			Set the gdb server listen port. (default port: 4242)
  -m, --multi
			Set gdb server to extended mode.
			st-util will continue listening for connections after disconnect.
  -n, --no-reset
			Do not reset board on connection.

The STLINKv2 device to use can be specified in the environment variable STLINK_DEVICE in the format <USB_BUS>:<USB_ADDR>.

Then, in your project directory, someting like this... (remember, you need to run an ARM gdb, not an x86 gdb)

$ arm-none-eabi-gdb fancyblink.elf
...
(gdb) tar extended-remote :4242
...
(gdb) load
Loading section .text, size 0x458 lma 0x8000000
Loading section .data, size 0x8 lma 0x8000458
Start address 0x80001c1, load size 1120
Transfer rate: 1 KB/sec, 560 bytes/write.
(gdb)
...
(gdb) continue

Resetting the chip from GDB

You may reset the chip using GDB if you want. You'll need to use `target extended-remote' command like in this session:

(gdb) target extended-remote localhost:4242
Remote debugging using localhost:4242
0x080007a8 in _startup ()
(gdb) kill
Kill the program being debugged? (y or n) y
(gdb) run
Starting program: /home/whitequark/ST/apps/bally/firmware.elf

Remember that you can shorten the commands. `tar ext :4242' is good enough for GDB.

Running programs from SRAM

You can run your firmware directly from SRAM if you want to. Just link it at 0x20000000 and do

(gdb) load firmware.elf

It will be loaded, and pc will be adjusted to point to start of the code, if it is linked correctly (i.e. ELF has correct entry point).

Writing to flash

The GDB stub ships with a correct memory map, including the flash area. If you would link your executable to 0x08000000 and then do

(gdb) load firmware.elf

then it would be written to the memory.

FAQ

Q: My breakpoints do not work at all or only work once.

A: Optimizations can cause severe instruction reordering. For example, if you are doing something like `REG = 0x100;' in a loop, the code may be split into two parts: loading 0x100 into some intermediate register and moving that value to REG. When you set up a breakpoint, GDB will hook to the first instruction, which may be called only once if there are enough unused registers. In my experience, -O3 causes that frequently.

Q: At some point I use GDB command `next', and it hangs.

A: Sometimes when you will try to use GDB next' command to skip a loop, it will use a rather inefficient single-stepping way of doing that. Set up a breakpoint manually in that case and do continue'.

Q: Load command does not work in GDB.

A: Some people report XML/EXPAT is not enabled by default when compiling GDB. Memory map parsing thus fail. Use --enable-expat.

Currently known working combinations of programmer and target

See doc/tested-boards.md

Known missing features

Some features are missing from the texane/stlink project and we would like you to help us out if you want to get involved:

Control programming speed (See #462)
OTP area programming (See #202)
EEPROM area programming (See #318)
Protection bits area reading (See #346)
MCU hotplug (See #449)
Writing options bytes (region) (See #458)
Instrumentation Trace Macro (ITM) Cell (See #136)
Writing external memory connected to an STM32 controller (e.g Quad SPI NOR flash) (See #412)

Known bugs

Sometimes flashing only works after a mass erase

There is seen a problem sometimes where a flash loader run error occurs and is resolved after mass-erase of the flash:

2015-12-09T22:01:57 INFO src/stlink-common.c: Successfully loaded flash loader in sram
2015-12-09T22:02:18 ERROR src/stlink-common.c: flash loader run error
2015-12-09T22:02:18 ERROR src/stlink-common.c: run_flash_loader(0x8000000) failed! == -1

Issue related to this bug: #356

Contributing and versioning

The semantic versioning scheme is used. Read more at semver.org
When creating a pull request, please open first a issue for discussion of new features. Bugfixes don't need a discussion.

License

The stlink library and tools are licensed under the BSD license. With some exceptions on external components (e.g flashloaders).

eblot/stlink