Glossary

Common terms and concepts in Zephyr development.

A

API (Application Programming Interface): Set of functions and macros that applications use to interact with Zephyr.
Atomic: Operations that complete without interruption, used for lock-free programming.

B

Board: Hardware platform definition including SoC and board-specific configurations.
BSP (Board Support Package): Collection of files that define a board’s hardware configuration.

C

CMake: Build system generator used by Zephyr to create build files.
Cooperative Thread: Thread with negative priority that only yields voluntarily.
CONFIG_*: Kconfig configuration symbols, prefixed with CONFIG_.

D

Device Tree (DTS): Data structure describing hardware configuration.
DEVICE_DT_DEFINE: Macro to define a device instance from device tree.
DT_ (macros)**: Device tree accessor macros like DT_NODELABEL, DT_PROP.

F

FIFO: First-in-first-out queue for passing data between threads.

G

GPIO (General Purpose Input/Output): Digital pins that can be configured as inputs or outputs.

H

HAL (Hardware Abstraction Layer): Layer that abstracts hardware-specific details.

I

I2C (Inter-Integrated Circuit): Two-wire serial bus for connecting peripherals.
ISR (Interrupt Service Routine): Function that handles hardware interrupts.

K

Kconfig: Configuration system inherited from Linux kernel.
Kernel Objects: Synchronization primitives like mutexes, semaphores, queues.
k_* (functions)**: Kernel API functions prefixed with k_.

L

LIFO: Last-in-first-out stack for data passing.

M

MCU (Microcontroller Unit): Integrated circuit with CPU, memory, and peripherals.
Mutex: Mutual exclusion object for protecting shared resources.
MSGQ (Message Queue): Fixed-size message passing mechanism.

P

Preemptive Thread: Thread that can be interrupted by higher priority threads.
Priority: Thread scheduling priority (lower number = higher priority).
prj.conf: Project configuration file for Kconfig options.

R

RTOS (Real-Time Operating System): Operating system with deterministic timing guarantees.

S

Scheduler: Kernel component that decides which thread runs.
Semaphore: Counting synchronization primitive.
SoC (System on Chip): Integrated circuit containing CPU and peripherals.
SPI (Serial Peripheral Interface): Four-wire serial bus for high-speed communication.
Spinlock: Busy-wait synchronization primitive, ISR-safe.

T

Thread: Basic unit of execution in Zephyr.
Tick: Basic time unit in the kernel (CONFIG_SYS_CLOCK_TICKS_PER_SEC).
Twister: Zephyr’s test framework.

U

UART (Universal Asynchronous Receiver-Transmitter): Serial communication interface.

W

West: Zephyr’s meta-tool for workspace management, building, and flashing.
Workqueue: Mechanism for deferred work execution in thread context.

Z

Zephyr SDK: Software Development Kit containing toolchains and tools.
Ztest: Unit testing framework for Zephyr applications.