RT-Thread is an open source IoT Real-Time Operating System (RTOS).

CMSIS-DSP embedded compute library for Cortex-M and Cortex-A

Bao, a Lightweight Static Partitioning Hypervisor

Gain an understanding of the fundamental topics and concepts of computer architecture including the application of these with modern Arm processors

ERIKA Enterprise v3 RTOS

rustBoot is a standalone bootloader written entirely in `Rust`, designed to run on anything from a microcontroller to a system on chip. It can be used to boot into bare-metal firmware or Linux.

Baremetal framework and example projects for the STM32MP15x Cortex-A7 based MPU

R3-OS — Experimental static (μITRON-esque) RTOS kernel for deeply embedded systems, testing the limit of Rust's compile-time evaluation and generics

Low level access to Cortex-A processors

Design, implement, and test an Arm Cortex-A-based SoCs on FPGA hardware using functional specifications, standard hardware description and software programming languages

Embedded firmware for ham radio transceivers

Productivity tool for populating an IAR Embedded Workbench project

Real-Time Operating System (RTOS) for Xilinx Zynq-7000 Cortex-A9 (ARMv7-A) multi-core SoCs (ZedBoard, PicoZed, MicroZed and similars) based on the ARINC 653 Part 1 specification

Bare metal Pine A64 / PinePhone Rust crates

Remote Configuration UI

L7 R7: SSD202/SSD201

armv7a bare-metal Rust support

ARM Cortex-A assembly projects for various Linux-based SBCs

ARM64 Architecture and Programming for Raspberry Pi 4B

Dave's real(time) operating systems :-)