Configure

oveRTOS uses Kconfig for build configuration, processed by the ove CLI. All configuration is stored in .config in the project root.

Interactive Configuration

make menuconfig

This opens the Kconfig TUI. Use arrow keys to navigate, space to toggle options, and ? to read help text. Save with S and exit with Q.

The top-level menu is organised into:

RTOS Selection — choose the backend
Hardware Target — choose the board
Toolchain — ARM cross-compiler source and settings
oveRTOS Modules — enable or disable individual API modules
Debug Options — log level, debug builds, stack canaries

Selecting the RTOS Backend

Under RTOS Selection > RTOS backend, choose one of:

Option	Backend
`FreeRTOS`	FreeRTOS via STM32CubeF7 SDK
`Zephyr RTOS`	Zephyr Project via West
`Apache NuttX`	Apache NuttX RTOS
`POSIX/SDL2 (native host)`	pthreads + SDL2, no cross-compilation

Enabling and Disabling Modules

Under oveRTOS Modules, each subsystem can be toggled independently. Two modules are always enabled (thread management and application lifecycle). The remaining modules are optional:

Module	Config symbol	Default
Synchronization primitives	`OVE_SYNC`	enabled
Audio streaming	`OVE_AUDIO`	enabled
Filesystem	`OVE_FS`	enabled
Console I/O	`OVE_CONSOLE`	enabled
Logging	`OVE_LOG`	enabled
Time and delays	`OVE_TIME`	enabled
Board descriptor	`OVE_BOARD`	enabled
GPIO	`OVE_GPIO`	enabled
LED control	`OVE_LED`	enabled
BSP compatibility shim	`OVE_BSP`	enabled
LVGL UI framework	`OVE_LVGL`	enabled
Message queues	`OVE_QUEUE`	enabled
Software timers	`OVE_TIMER`	enabled
Event groups	`OVE_EVENTGROUP`	enabled
Interactive shell	`OVE_SHELL`	enabled
Non-volatile storage	`OVE_NVS`	enabled
Watchdog timer	`OVE_WATCHDOG`	enabled
Work queues	`OVE_WORKQUEUE`	disabled
Stream I/O	`OVE_STREAM`	disabled

Zero-Heap Mode

At the bottom of oveRTOS Modules, enable Zero-heap build (OVE_ZERO_HEAP) to switch _create()/_destroy() from heap-backed functions to GCC statement-expression macros that auto-generate per-call-site static storage. Application code using _create()/_destroy() continues to work unchanged. Use _init()/_deinit() when you need explicit storage control (arrays, loops, structs). In zero-heap mode, size parameters must be compile-time constants and each _create() call site produces one static object.

Backend-Specific Submenus

After selecting a backend, a dedicated menu appears with source method and kernel configuration options. For advanced NuttX or Zephyr kernel tuning, use the dedicated targets:

make nuttx-menuconfig   # NuttX native kernel config TUI
make zephyr-menuconfig  # Zephyr native kernel config TUI

Loading a Defconfig

Defconfigs are pre-made configurations for specific board and RTOS combinations. Load one to get a working starting point:

make <name>_defconfig

For example:

make qemu_freertos_example_c_defconfig
make stm32f746_zephyr_example_cpp_defconfig
make host_posix_example_rust_defconfig

Available Defconfigs

host (POSIX native)

Defconfig	Description
`host_posix_example_c_defconfig`	C example, POSIX backend
`host_posix_example_c_zeroheap_defconfig`	C example, POSIX, zero-heap
`host_posix_example_cpp_defconfig`	C++ example, POSIX backend
`host_posix_example_cpp_zeroheap_defconfig`	C++ example, POSIX, zero-heap
`host_posix_example_rust_defconfig`	Rust example, POSIX backend
`host_posix_example_rust_zeroheap_defconfig`	Rust example, POSIX, zero-heap
`host_posix_example_zig_defconfig`	Zig example, POSIX backend
`host_posix_example_zig_zeroheap_defconfig`	Zig example, POSIX, zero-heap
`host_posix_benchmark_defconfig`	C Benchmark, POSIX backend
`host_posix_benchmark_zeroheap_defconfig`	C Benchmark, POSIX, zero-heap
`host_posix_benchmark_cpp_defconfig`	C++ Benchmark, POSIX backend
`host_posix_benchmark_rust_defconfig`	Rust Benchmark, POSIX backend
`host_posix_benchmark_zig_defconfig`	Zig Benchmark, POSIX backend

qemu (QEMU MPS2-AN500 Cortex-M7)

Defconfig	Description
`qemu_freertos_example_c_defconfig`	C example, FreeRTOS
`qemu_freertos_example_c_zeroheap_defconfig`	C example, FreeRTOS, zero-heap
`qemu_freertos_example_cpp_defconfig`	C++ example, FreeRTOS
`qemu_freertos_example_cpp_zeroheap_defconfig`	C++ example, FreeRTOS, zero-heap
`qemu_freertos_example_rust_defconfig`	Rust example, FreeRTOS
`qemu_freertos_example_rust_zeroheap_defconfig`	Rust example, FreeRTOS, zero-heap
`qemu_freertos_example_zig_defconfig`	Zig example, FreeRTOS
`qemu_freertos_example_zig_zeroheap_defconfig`	Zig example, FreeRTOS, zero-heap
`qemu_freertos_benchmark_defconfig`	Benchmark, FreeRTOS
`qemu_freertos_benchmark_zeroheap_defconfig`	Benchmark, FreeRTOS, zero-heap
`qemu_nuttx_example_c_defconfig`	C example, NuttX
`qemu_nuttx_example_c_zeroheap_defconfig`	C example, NuttX, zero-heap
`qemu_nuttx_example_cpp_defconfig`	C++ example, NuttX
`qemu_nuttx_example_cpp_zeroheap_defconfig`	C++ example, NuttX, zero-heap
`qemu_nuttx_example_rust_defconfig`	Rust example, NuttX
`qemu_nuttx_example_rust_zeroheap_defconfig`	Rust example, NuttX, zero-heap
`qemu_nuttx_example_zig_defconfig`	Zig example, NuttX
`qemu_nuttx_example_zig_zeroheap_defconfig`	Zig example, NuttX, zero-heap
`qemu_nuttx_benchmark_defconfig`	Benchmark, NuttX
`qemu_nuttx_benchmark_zeroheap_defconfig`	Benchmark, NuttX, zero-heap
`qemu_zephyr_example_c_defconfig`	C example, Zephyr
`qemu_zephyr_example_c_zeroheap_defconfig`	C example, Zephyr, zero-heap
`qemu_zephyr_example_cpp_defconfig`	C++ example, Zephyr
`qemu_zephyr_example_cpp_zeroheap_defconfig`	C++ example, Zephyr, zero-heap
`qemu_zephyr_example_rust_defconfig`	Rust example, Zephyr
`qemu_zephyr_example_rust_zeroheap_defconfig`	Rust example, Zephyr, zero-heap
`qemu_zephyr_example_zig_defconfig`	Zig example, Zephyr
`qemu_zephyr_example_zig_zeroheap_defconfig`	Zig example, Zephyr, zero-heap
`qemu_zephyr_benchmark_defconfig`	Benchmark, Zephyr
`qemu_zephyr_benchmark_zeroheap_defconfig`	Benchmark, Zephyr, zero-heap

stm32f746 (STM32F746G-Discovery)

Defconfig	Description
`stm32f746_freertos_example_c_defconfig`	C example, FreeRTOS
`stm32f746_freertos_example_c_zeroheap_defconfig`	C example, FreeRTOS, zero-heap
`stm32f746_freertos_example_cpp_defconfig`	C++ example, FreeRTOS
`stm32f746_freertos_example_cpp_zeroheap_defconfig`	C++ example, FreeRTOS, zero-heap
`stm32f746_freertos_example_rust_defconfig`	Rust example, FreeRTOS
`stm32f746_freertos_example_rust_zeroheap_defconfig`	Rust example, FreeRTOS, zero-heap
`stm32f746_freertos_example_zig_defconfig`	Zig example, FreeRTOS
`stm32f746_freertos_example_zig_zeroheap_defconfig`	Zig example, FreeRTOS, zero-heap
`stm32f746_freertos_benchmark_defconfig`	Benchmark, FreeRTOS
`stm32f746_freertos_benchmark_zeroheap_defconfig`	Benchmark, FreeRTOS, zero-heap
`stm32f746_nuttx_example_c_defconfig`	C example, NuttX
`stm32f746_nuttx_example_c_zeroheap_defconfig`	C example, NuttX, zero-heap
`stm32f746_nuttx_example_cpp_defconfig`	C++ example, NuttX
`stm32f746_nuttx_example_cpp_zeroheap_defconfig`	C++ example, NuttX, zero-heap
`stm32f746_nuttx_example_rust_defconfig`	Rust example, NuttX
`stm32f746_nuttx_example_rust_zeroheap_defconfig`	Rust example, NuttX, zero-heap
`stm32f746_nuttx_example_zig_defconfig`	Zig example, NuttX
`stm32f746_nuttx_example_zig_zeroheap_defconfig`	Zig example, NuttX, zero-heap
`stm32f746_nuttx_benchmark_defconfig`	Benchmark, NuttX
`stm32f746_zephyr_example_c_defconfig`	C example, Zephyr
`stm32f746_zephyr_example_c_zeroheap_defconfig`	C example, Zephyr, zero-heap
`stm32f746_zephyr_example_cpp_defconfig`	C++ example, Zephyr
`stm32f746_zephyr_example_cpp_zeroheap_defconfig`	C++ example, Zephyr, zero-heap
`stm32f746_zephyr_example_rust_defconfig`	Rust example, Zephyr
`stm32f746_zephyr_example_rust_zeroheap_defconfig`	Rust example, Zephyr, zero-heap
`stm32f746_zephyr_example_zig_defconfig`	Zig example, Zephyr
`stm32f746_zephyr_example_zig_zeroheap_defconfig`	Zig example, Zephyr, zero-heap
`stm32f746_zephyr_benchmark_defconfig`	Benchmark, Zephyr
`stm32f746_zephyr_benchmark_zeroheap_defconfig`	Benchmark, Zephyr, zero-heap

Run make help to see the list at any time.

Saving a Modified Configuration

After customising settings in menuconfig, save the minimal diff as a new defconfig:

make savedefconfig