You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
45 lines
1.8 KiB
Markdown
45 lines
1.8 KiB
Markdown
# stmos
|
|
|
|
stmos is an attempt to implement a general-purpose operating system on ARM
|
|
microcontrollers. The name "stmos" is due to the fact that this was first
|
|
implemented on an STM32L476RG MCU (ARM Cortex-M4F), and the operating system
|
|
still includes many operations/values that are specific to this processor
|
|
(currently limiting the portability of this OS).
|
|
|
|
Eventually, this OS aims to support at least all Cortex-M MCUs.
|
|
|
|
Features:
|
|
* Advanced heap that does its best to keep large chunks of memory available
|
|
* Round-robin multitasking that keeps tasks in userspace
|
|
* A virtual filesystem implementation with stdio/initrd built into the kernel
|
|
* Ability to execute ELF files loaded from the filesystem
|
|
* A nearly complete C standard library implementation available to loaded ELFs
|
|
(using [PDCLib](https://github.com/DevSolar/pdclib))
|
|
* libgpio: The first userspace library; makes GPIO available to loaded ELFs
|
|
|
|
Currently supported processors:
|
|
* STM32L476RG (board: NUCLEO-L476RG)
|
|
|
|
### building
|
|
To build stmos, you'll need the following programs:
|
|
* The arm-stmos toolchain (see the `arm-stmos` folder)
|
|
* openocd
|
|
* gdb (with multiarch support, `gdb-multiarch` on Debian)
|
|
|
|
To compile stmos simply run `make` (-j supported). To upload, use `run.sh` to
|
|
launch OpenOCD and GDB; then, do `lo` to load stmos, and `c` to begin execution.
|
|
|
|
### notes
|
|
Currently, the only available filesystem driver is for the initrd. Files in the
|
|
folder `src/initrd/files` are put into the initrd. C source files in
|
|
`src/initrd` are compiled (with libgpio available), placing the programs in
|
|
`src/initrd/files`
|
|
|
|
What's next for stmos?
|
|
* Processor independence
|
|
* SD card support?
|
|
* Display support? (ILI....)
|
|
* Support for running a popular program (e.g. a shell like sash, maybe lua)
|
|
* Growth of features available to loaded ELFs (better execve, signals?, etc.)
|
|
|