Files
micropython/ports/bare-arm
Damien George a3f9dec788
Some checks failed
JavaScript code lint and formatting with Biome / eslint (push) Has been cancelled
Check code formatting / code-formatting (push) Has been cancelled
Check spelling with codespell / codespell (push) Has been cancelled
Build docs / build (push) Has been cancelled
Check examples / embedding (push) Has been cancelled
Package mpremote / build (push) Has been cancelled
.mpy file format and tools / test (push) Has been cancelled
Build ports metadata / build (push) Has been cancelled
alif port / build_alif (alif_ae3_build) (push) Has been cancelled
cc3200 port / build (push) Has been cancelled
esp32 port / build_idf (esp32_build_c2_c6) (push) Has been cancelled
esp32 port / build_idf (esp32_build_cmod_spiram_s2) (push) Has been cancelled
esp32 port / build_idf (esp32_build_s3_c3) (push) Has been cancelled
esp8266 port / build (push) Has been cancelled
mimxrt port / build (push) Has been cancelled
nrf port / build (push) Has been cancelled
powerpc port / build (push) Has been cancelled
qemu port / build_and_test_arm (bigendian) (push) Has been cancelled
qemu port / build_and_test_arm (sabrelite) (push) Has been cancelled
qemu port / build_and_test_arm (thumb) (push) Has been cancelled
qemu port / build_and_test_rv32 (push) Has been cancelled
renesas-ra port / build_renesas_ra_board (push) Has been cancelled
rp2 port / build (push) Has been cancelled
samd port / build (push) Has been cancelled
stm32 port / build_stm32 (stm32_misc_build) (push) Has been cancelled
stm32 port / build_stm32 (stm32_nucleo_build) (push) Has been cancelled
stm32 port / build_stm32 (stm32_pyb_build) (push) Has been cancelled
unix port / minimal (push) Has been cancelled
unix port / reproducible (push) Has been cancelled
unix port / standard (push) Has been cancelled
unix port / standard_v2 (push) Has been cancelled
unix port / coverage (push) Has been cancelled
unix port / coverage_32bit (push) Has been cancelled
unix port / nanbox (push) Has been cancelled
unix port / longlong (push) Has been cancelled
unix port / float (push) Has been cancelled
unix port / gil_enabled (push) Has been cancelled
unix port / stackless_clang (push) Has been cancelled
unix port / float_clang (push) Has been cancelled
unix port / settrace_stackless (push) Has been cancelled
unix port / macos (push) Has been cancelled
unix port / qemu_mips (push) Has been cancelled
unix port / qemu_arm (push) Has been cancelled
unix port / qemu_riscv64 (push) Has been cancelled
unix port / sanitize_address (push) Has been cancelled
unix port / sanitize_undefined (push) Has been cancelled
webassembly port / build (push) Has been cancelled
windows port / build-vs (Debug, x64, dev, 2017, [15, 16)) (push) Has been cancelled
windows port / build-vs (Debug, x64, dev, 2022, [17, 18)) (push) Has been cancelled
windows port / build-vs (Debug, x86, dev, 2017, [15, 16)) (push) Has been cancelled
windows port / build-vs (Debug, x86, dev, 2022, [17, 18)) (push) Has been cancelled
windows port / build-vs (Release, x64, dev, 2017, [15, 16)) (push) Has been cancelled
windows port / build-vs (Release, x64, dev, 2019, [16, 17)) (push) Has been cancelled
windows port / build-vs (Release, x64, dev, 2022, [17, 18)) (push) Has been cancelled
windows port / build-vs (Release, x64, standard, 2017, [15, 16)) (push) Has been cancelled
windows port / build-vs (Release, x64, standard, 2019, [16, 17)) (push) Has been cancelled
windows port / build-vs (Release, x64, standard, 2022, [17, 18)) (push) Has been cancelled
windows port / build-vs (Release, x86, dev, 2017, [15, 16)) (push) Has been cancelled
windows port / build-vs (Release, x86, dev, 2019, [16, 17)) (push) Has been cancelled
windows port / build-vs (Release, x86, dev, 2022, [17, 18)) (push) Has been cancelled
windows port / build-vs (Release, x86, standard, 2017, [15, 16)) (push) Has been cancelled
windows port / build-vs (Release, x86, standard, 2019, [16, 17)) (push) Has been cancelled
windows port / build-vs (Release, x86, standard, 2022, [17, 18)) (push) Has been cancelled
windows port / build-mingw (i686, mingw32, dev) (push) Has been cancelled
windows port / build-mingw (i686, mingw32, standard) (push) Has been cancelled
windows port / build-mingw (x86_64, mingw64, dev) (push) Has been cancelled
windows port / build-mingw (x86_64, mingw64, standard) (push) Has been cancelled
windows port / cross-build-on-linux (push) Has been cancelled
zephyr port / build (push) Has been cancelled
Python code lint and formatting with ruff / ruff (push) Has been cancelled
py/mpconfig: Enable the sys module at all feature levels by default.
This is a pretty fundamental module, and even minimal ports like unix and
zephyr minimal have it enabled.  So, enabled it by default at the lowest
feature level.

Most things in the `sys` module are configurable, and off by default, so it
shouldn't add too much to ports that don't already have it enabled (which
is just the minimal port).

Also note that `sys` is still disabled on the bare-arm port, to keep that
ultra minimal.  It means we now have bare-arm without `sys` and the minimal
port with `sys`.  That will allow different code size comparisons if/when
new `sys` features are added.

Signed-off-by: Damien George <damien@micropython.org>
2025-08-22 13:31:10 +10:00
..

The bare-arm port

This port is intended to be the bare-minimum amount of code and configuration required to get MicroPython compiling and running on a bare-metal ARM-based target. No external dependencies or libraries are needed for this build and it shows exactly what hardware and system functionality MicroPython needs to run.

To build, simply run make in this directory. The output will be build/firmware.elf (and also corresponding .bin and .dfu files). This firmware can run on an STM32F405-based board (eg a PYBv1.x) and make deploy will program it to such an MCU when put in USB DFU mode. The output is a UART at 115200 baud, with TX on PA0.

There are some simple demonstration code strings (see main.c) which are compiled and executed when the firmware starts. They produce output on the system's stdout.

The size of the firmware (the machine code that is programmed to the microcontroller's flash/ROM) is currently around 56500 bytes.