{"id":12,"date":"2019-12-08T01:37:57","date_gmt":"2019-12-08T00:37:57","guid":{"rendered":"http:\/\/pmortensen.eu\/2\/?p=12"},"modified":"2023-11-08T15:11:18","modified_gmt":"2023-11-08T14:11:18","slug":"arm-toolchain-ubuntu-19-04-black-magic-probe","status":"publish","type":"post","link":"https:\/\/pmortensen.eu\/world2\/2019\/12\/08\/arm-toolchain-ubuntu-19-04-black-magic-probe\/","title":{"rendered":"Getting the ARM toolchain to work on Ubuntu 19.04 and later (including for Black Magic Probe (BMP))"},"content":{"rendered":"

The short version is: Download the tar ball from arm.com, extract, add the \/bin folder in the extracted to the path, and make GDB<\/a> work by adding symbolic links in \/usr\/lib\/x86_64-linux-gnu for the expected version 5 of the libraries “libncurses” and “libtinfo” (to point to the existing\/newest versions of those libraries).<\/p>\n

Introduction<\/h2>\n

This post contains complete instructions to set up the GCC cross-compiler from scratch on a newly installed Ubuntu 19.04<\/a> (Disco Dingo) or later (no extra packages assumed to be installed), compiling a “Hello, World!” (LED blink) program for an ARM board (1Bitsy<\/a>), flashing it to the board using GDB and the Black Magic Probe<\/a>, and interactively single-stepping the program in GDB.<\/p>\n

The installation part is completely general and the LED blink part only requires specifying another processor (as the used library works on multiple ARM processors). The flash and debugging part in GDB is dependent on an adapter that implements the GDB debugging protocol (Black Magic Probe is used as an example here).<\/p>\n

Only the last part is specific for Black Magic Probe.<\/p>\n

The problem<\/h2>\n

A previous blog post<\/a> covered using apt-get to install the GCC cross-compiler for ARM:<\/p>\n

\r\nsudo add-apt-repository ppa:team-gcc-arm-embedded\/ppa\r\nsudo apt-get update\r\nsudo apt-get install gcc-arm-embedded\r\n<\/pre>\n
While this still works on Ubuntu 18.04 (32 bit) and Ubuntu 16.04 (64 bit), it no longer works on Ubuntu 19.04 and later:<\/p>\n
\r\nE: Unable to locate package gcc-arm-embedded\r\n<\/pre>\n
Even when using the new procedure to get the compiler to run, there are also problems getting GDB to run. For further details, see Appendix A.<\/p>\n
Step-by-step procedure<\/h2>\n
The following can be blindly applied. It has been tested on a 64-bit Ubuntu MATE 20.04<\/a> (Focal Fossa) system and a 64-bit Ubuntu 19.10 (Eoan Ermine) system and is likely to also work on a 64-bit Ubuntu 19.04 (Disco Dingo) system.<\/p>\n
Setting up the cross compiler<\/h3>\n
Before starting, uninstall any already-installed ARM GCC cross compiler (this command can be used unconditionally – if it is not installed, it will report “Package ‘gcc-arm-none-eabi’ is not installed, so not removed”):<\/p>\n
\r\nsudo apt remove gcc-arm-embedded\r\n<\/pre>\n
Instead of using apt-get, we get the toolchain directly from arm.com as a tar ball. This is actually much simpler than it sounds: Download it, extract it, and add the location of the \/bin folder in the extracted folder to the path (environment variable “PATH”). That’s it. In detail:<\/p>\n
In the following, the sample path “\/temp2\/2019-12-05” under the current user is used to download and extract into. You may want some other folder(s) – adjust as needed.<\/p>\n
Go to arm.com<\/a> and find “Linux x86_64 Tarball”. Download “gcc-arm-none-eabi-9-2019-q4-major-x86_64-linux.tar.bz2” to ~\/temp2\/2019-12-05 (direct download URL<\/a> (valid as of 2019-12-07)), MD5 FE0029DE4F4EC43CF7008944E34FF8CC. It is about 110 MB.<\/p>\n
Extract it. For example, in Nautilus (the default file manager in Ubuntu), right click on the .bz2 file, select “Open with Archive Manager”, select the single folder, right click on it, select “Extract”, press button “Extract”, wait for it to finish, “Close”, and close Archive Manager.<\/p>\n
Alternatively, on the command line:<\/p>\n
\r\ncd ~\/temp2\/2019-12-05\r\ntar xvzf gcc-arm-none-eabi-9-2019-q4-major-x86_64-linux.tar.bz2\r\n<\/pre>\n
Install other required packages:<\/p>\n
\r\nsudo apt-get update\r\nsudo apt-get install ncurses-dev\r\nsudo apt-get install git\r\nsudo apt-get install make\r\nsudo apt-get install python-minimal\r\n<\/pre>\n
For initial testing (in the same session), this suffices:<\/p>\n
\r\ncd ~\r\nexport PATH=$PATH:~\/temp2\/2019-12-05\/gcc-arm-none-eabi-9-2019-q4-major\/bin\r\narm-none-eabi-c++  --version\r\n<\/pre>\n
The output should look something like this:<\/p>\n
\r\narm-none-eabi-c++ (GNU Tools for Arm Embedded Processors 9-2019-q4-major) 9.2.1 20191025 (release) [ARM\/arm-9-branch revision 277599]\r\nCopyright (C) 2019 Free Software Foundation, Inc.\r\nThis is free software; see the source for copying conditions.  There is NO\r\nwarranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\r\n<\/pre>\n
For more permanent use, put this into the .profile file, near the end, in the user top folder, using some text editor (Vim<\/a>\/vi<\/a> in this example – but you need to be proficient in using Vim\/vi. Otherwise, use another editor, like nano<\/a> or Geany<\/a>):<\/p>\n
\r\nvi ~\/.profile\r\n<\/pre>\n
\r\nPATH=$PATH:~\/temp2\/2019-12-05\/gcc-arm-none-eabi-9-2019-q4-major\/bin\r\n<\/pre>\n
After the change, it may be necessary to login\/logout or restart the computer<\/em><\/strong> to make the change take effect (it may not be enough to open a new terminal window).<\/p>\n
Compiling the blink program<\/h3>\n
Get source code for a Hello, World!<\/em> (blink) example program:<\/p>\n
\r\ncd ~\r\ngit clone https:\/\/github.com\/1bitsy\/1bitsy-examples.git\r\ncd 1bitsy-examples\r\ngit submodule init\r\ngit submodule update\r\n<\/pre>\n
<\/div>\n
On Ubuntu 20.04 and later, change \u201cpython\u201d in the very first line of file “irq2nvic_h” to \u201cpython3\u201d (see the appendix for details):<\/p>\n
\r\nvi ~\/1bitsy-examples\/libopencm3\/scripts\/irq2nvic_h\r\n<\/pre>\n
Compile:<\/p>\n
\r\nmake\r\n<\/pre>\n
Check that it produced the executable:<\/p>\n
\r\nls -ls ~\/1bitsy-examples\/examples\/1bitsy\/fancyblink\/*.elf\r\n<\/pre>\n
The result should be something like (broken up in two lines here):<\/p>\n
\r\n112 -rwxrwxr-x 1 embo embo 234364 Jan 19 19:19 \r\n\/home\/embo\/1bitsy-examples\/examples\/1bitsy\/fancyblink\/fancyblink.elf\r\n<\/pre>\n
Getting GDB to work<\/h3>\n
This presumes the current version of “libncurses” and “libtinfo” is 6.2 (“libncurses.so.6.2” (160 KB) and “libtinfo.so.6.2” (190 KB) exist in folder “\/usr\/lib\/x86_64-linux-gnu”). If not, adjust the version numbers accordingly (in Ubuntu 19.10, the version is 6.1 instead of 6.2.)<\/p>\n
\r\ncd \/usr\/lib\/x86_64-linux-gnu\r\nsudo ln -s libncurses.so.6.2 libncurses.so.5\r\nsudo ln -s libtinfo.so.6.2   libtinfo.so.5\r\n<\/pre>\n
This puts in symbolic links for the libraries GDB is expecting (version 5).<\/p>\n
Verify:<\/p>\n
\r\nls -ls \/usr\/lib\/x86_64-linux-gnu | grep libncurses.so.5\r\nls -ls \/usr\/lib\/x86_64-linux-gnu | grep libtinfo.so.5\r\n<\/pre>\n
The output should look like:<\/p>\n
\r\n0 lrwxrwxrwx  1 root root 17 Jan 19 15:38 libncurses.so.5 -> libncurses.so.6.2\r\n0 lrwxrwxrwx  1 root root 15 Jan 19 15:38 libtinfo.so.5 -> libtinfo.so.6.2\r\n<\/pre>\n
Check that GDB works:<\/p>\n
\r\narm-none-eabi-gdb --version\r\n<\/pre>\n
The output should be something like:<\/p>\n
\r\nGNU gdb (GNU Tools for Arm Embedded Processors 9-2019-q4-major) 8.3.0.20190709-git\r\nCopyright (C) 2019 Free Software Foundation, Inc.\r\nLicense GPLv3+: GNU GPL version 3 or later <http:\/\/gnu.org\/licenses\/gpl.html>\r\nThis is free software: you are free to change and redistribute it.\r\nThere is NO WARRANTY, to the extent permitted by law.\r\n<\/pre>\n
Setting up for hardware<\/h3>\n
\r\nid\r\nsudo adduser $USER dialout\r\nid\r\n<\/pre>\n
(Related Ask Ubuntu question<\/a>. The reason why it is “dialout”<\/em><\/a>.)<\/sub><\/p>\n
The output should include “(dialout)” in the “groups=” part. In that case, log out and log in. If it is not in the output, a restart of the computer is required (if a restart is not done the result is “Permission denied” in the “target extended-remote \/dev\/ttyACM0” line below).<\/p>\n
Connect the Black Magic Probe with a microUSB cable.<\/p>\n
\r\nclear ; dmesg | tail -n 15\r\n<\/pre>\n
Output includes: “ttyACM0” and “ttyACM1”. “ttyACM0” is the COM port<\/a> that GDB uses to communicate with the Black Magic Probe and “ttyACM1” is the auxiliary COM port that can be used to connect to the target board’s serial port (so it is not necessary to use a separate USB-to-serial adapter).<\/p>\n
Note that if some device with a serial port, for example, an Arduino, was already connected, the numbers may<\/em> be shifted (it all depends), “ttyACM1” and “ttyACM2”. An example could be a macro keyboard based on Arduino Leonardo or a keyboard based on QMK<\/a> (also macro capable).<\/p>\n
Connect the 1Bitsy with a microUSB cable.<\/p>\n
\r\nclear ; dmesg | tail -n 15\r\n<\/pre>\n
Output includes: “ttyACM2” – but only<\/em> if there is already firmware on it that makes it appear as a serial device. This is not<\/em> the case for the Kickstarter one<\/a>… <\/p>\n
Connect 1Bitsy and Black Magic Probe using the JTAG cable. Note: the ribbon cable is to come from the same direction<\/em> as the USB cable. That is, the ribbon cable should not<\/strong><\/em> cover the main chip\/IC of the 1Bitsy.<\/p>\n
Flashing the blink program<\/h3>\n
\r\ncd ~\/1bitsy-examples\/examples\/1bitsy\/fancyblink\r\narm-none-eabi-gdb fancyblink.elf\r\ntarget extended-remote \/dev\/ttyACM0\r\nmonitor version\r\nmonitor help\r\nmonitor jtag_scan\r\nattach 1\r\nload\r\n<\/pre>\n
Debugging with GDB<\/h3>\n
\r\nrun\r\ny\r\n<Ctrl + C>\r\nlist\r\n<\/pre>\n
Note: ‘run’ (or ‘start’ or repowering) is required if updating\/changing the source code. The changes do not take effect before restarting, that is, flashing (‘load’ in the previous step) will not actually make it start execute the newly flashed program (the old one is still RAM and is still executing).<\/p>\n
Debugging in full-screen mode<\/h3>\n
Using a line debugger is like being trapped in the 1970s. However, GDB can also do full-screen debugging.<\/p>\n
It can also be put into a mode when Enter<\/kbd> does not have to be pressed for each command. Thus it can come close to an experience of what is expected of a debugger.<\/p>\n
Enable full-screen mode:<\/p>\n
\r\ntui enable\r\n<\/pre>\n
It immediately shows a screen with about 10 lines on each side of the current line:<\/p>\n
\"Screen<\/p>\n
Enable single key mode: Ctrl<\/kbd> + X<\/kbd>, C<\/kbd><\/p>\n
Exit single key mode: Q<\/kbd><\/p>\n
Continue, break into the running program (on the 1Bitsy), and do some step over and step in operations:<\/p>\n
\r\ncont\r\n<Ctrl + C>\r\nstep\r\nstart\r\ny\r\nnext\r\nstep\r\nnext\r\nnext\r\nnext\r\ncont\r\n<\/pre>\n
In GDB, <\/p>\n