Embedded Interview Questions

Interview Questions Archive by Company

Coding Interview University

A complete computer science study plan to become a software engineer.

EA-SKILL

16 Essential Skills for Embedded Engineer

How to be low-level programmer

Programmer Competency Matrix

Integer size in C on 32-bit and 64-bit system

TeraTerm - TTL command reference

TeraTerm Scripts

Linker Command File Primer

The C build process

Building Bare-Metal ARM Systems with GNU

ELF – Executable and Linkable Format

Toolchains

What is an application binary interface (ABI)?

ARM Cortex M4 Blink Example (Linker Script)

A Sample Linker Script

Linking and Loading

Embedded Software _ Getting started

How to convert from an armlink scatter file to a GNU ld linker script

Using the GNU Linker

Everything You Never Wanted To Know About Linker Script

Modern Embedded Systems Programming Course

Learn from the basics to modern embedded programming practice.

McuOnEclipse

Everything about Eclipse, microcontrollers, software and tools.

Simplest bare metal program for ARM

(table of content)

Bare metal programming guide

a detailed guide for beginners

Real-Time C++

companion bare-metal code to Real-Time C++ book.

hypervisor

ARM64 Type-1 bare-metal hypervisor in no_std Rust, runs at EL2 on QEMU virt, boots Linux with FF-A v1.1 SPMC.

MSP430-GCC

CS4101: Introduction to Embedded Systems

The course is designed around labs, using TI MSP430 LaunchPad and Arduino Uno to discuss concepts such as basic I/O, timing and clocking, interrupt handling, serial communication, embedded operating systems, synchronization, etc.

msp430-template

A template for MSP430 firmware.

MSP430 reference

EmbeddedSystems.Playground

Macros in TivaWare

Analog to Digital Conversion, Data Acquisition and Control

Embedded Systems - Shape The World

HowTo: Develop on the TI Tiva LaunchPad using Linux

Linux command line build system to generate binaries for TM4C123 (ARM Cortex M4)

The complete tutorial for Stellaris LaunchPad development with GNU/Linux (I)

Getting Started with the TI Stellaris LaunchPad on Linux

Embedded Systems with TM4C123 @Valvano

Create FreeRTOS Demo Project using the GCC Compiler

Serial bootloader on TM4C12x Microcontroller

Tivaware bootloader

Diagnosing Common Development Problems and Tips & Info for TM4C Devices

FreeRTOS-GCC-tm4c123glx

A port of FreeRTOS to the Texas Instruments Tiva TM4C123GLX Launchpad.

Stellaris_TM4C123G_GCC_Template

Texas Instruments template project for the TM4C123 series using GNU toolchain.

tm4c-gcc

TM4C123 GCC project template.

tivaapps

Example hello-world apps for Texas Instruments TI-RTOS for Tiva C using a Linux host

Drivers and examples

Drivers for internal peripherals and external modules for Tiva C, examples of FreeRTOS features under development/FreeRTOS

Real-Time Bluetooth Networks - UTAustinX

Learn the design fundamentals of a real-time operating system (RTOS) and how to build a Bluetooth network in this hands-on project-based course.

STM32 bootloader

Tests to program STM32 Nucleo in C with GCC ARM embedded toolchain and libopencm3

A demo project of FreeRTOS running on a STM32F4 Discovery board.

DFU Bootloader for STM32 chips

Customizable Bootloader for STM32 microcontrollers.

Lightweight USB device Stack for STM32 microcontrollers

Lightweight USB device Stack for STM32 microcontrollers.

STM32 programming with Embedded GNU Compiler

A tiny portable 3D graphics lib for micro controllers (Oled display)

Getting started with the STM32F4-Discovery board using the EmBitz IDE

libopencm3 and FreeRTOS projects using the STM32F103C8T6 MCU

A template for building STM32F0 ARM projects with GCC

Open source flash program for STM32 using the ST serial bootloader

Standalone TCP/IP stack for STM32, bare metal or RTOS

is a networking library for C/C++. It implements event-driven non-blocking APIs for TCP, UDP, HTTP, WebSocket, MQTT. It is designed for connecting devices and bringing them online.

stm32-hid-bootloader

Driverless USB HID bootloader and flashing tool for STM32F10X devices

stm32l1xx-template

A template for building firmware for the STM32L1xx.

STM32F103C8 Examples

stm32f103

Bare metal programming on a generic STM32F103c8 board

stm32_samples

stm32f4de example code

stm32f4xx with Rust at the HAL

A series of tutorials for building STM32F4xx applications with Rust.

stm32-rf-scanner

STM32 and nRF24L01+ based 2.4GHz RF scanner

stm32-dc-dc

STM32 based DC-DC converter

rustlink

small set of Rust tools to program STM32 devices

stm32-async-1wire

Non-blocking, register-level 1-Wire master for STM32 (DS18B20 temperature driver on top). Hardware-timed (TIM1+DMA, DMAMUX on G0), interrupt-free, RTOS-agnostic; header-only backends for STM32F1/F0/G0; hardware-validated on Blue Pill (F103) and STM32G031; strong-pull-up parasite powering; released…

SD Card OVID Player

STM32F103 SD card frame-video player for SSD1306/SH1106 OLED, with FatFs file browsing and a Windows media converter.

STM32F7 Series

STM32 eLinux

STM32F7 os.mbed

stm8-bare-min

Tiny peripheral library for STM8S

stm8-bootloader

Serial bootloader for STM8S microcontrollers

stm8-multi-tasker

STM8-Multi-Tasker - Preemptive/Cooperative Round Robin Scheduler for STM8

Wolk STM8 stuff

STM8S001J3_tiny_board

A tiny dev board for STM8S001J3 MCU designed in KiCad.

An open source bootloader for the ESP8266

An esp8266 rom creation tool

Wi-FI ESP8266 learning journey

Wi-FI ESP32 learning journey

Sming - ESP8266/ESP32 IoT Framework

Sming is an asynchronous C/C++ framework with superb performance and multiple network features. Sming is open source and is tailored towards embedded devices.

Raspberry Pi Bare Metal

& related link

ChibiOS/RT on the Raspberry Pi

Raspberry Pi ARM based bare metal examples

Bare metal Raspberry Pi 3 tutorials

Bare metal Raspberry Pi 3 tutorials

Open Projects: Raspberry, Beaglebone BSP

A Real-Time Operating System on the Raspberry Pi

A port of FreeRTOS to the raspberry pi

FreeRTOS Successfully Ported

Exploring AArch64 assembler - Raspberry

A bootloader for the Raspberry Pi using the ethernet device

Bare Metal Raspberry Pi

Bare Metal Programming in C

Baking Pi – Operating Systems Development

by University of Cambridge

Search for 'Raspberry' topic on Github

elinux: Raspberry Pi Programming

or elinux: RPi Hub

Stanford CS104e - An Experimental Course on Operating Systems

Computer Systems

Build a Debian-based ARM64 system for Raspberry Pi 3

Learning operating system development using Linux kernel and Raspberry Pi

Learning operating system development using Linux kernel and Raspberry Pi

A port of FreeRTOS to the raspberry pi 2B. With USB+Ethernet+TCP/IP.

64-bit Tiano Core UEFI for the Raspberry Pi 3

DEPRECATED - DO NOT USE | Go here instead ->

CXCORE-RaspberryPi3-ubuntu-18.04-aarch64

Sample source: Baremetal source code for Raspberry

Sample source: NarcOS - A bare metal ultralight kernel for Raspberry Pi 3

Sample source: FreeRTOS v9.0.0 port for Raspberry Pi 1

Sample source: A bare-metal experiments with the RaspberryPi

「BareMetalで遊ぶ Raspberry Pi」のプログラムです。

UEFI for RaspberryPi2 and RaspberryPi3 based on Linaro EDK2

ARM-episodes

& ARM exploitation for IoT

ARM shellcode and exploit development - BSidesMunich 2018

64 bit Bare Metal Programming on RPI-3

Raspberry Pi 3 Bare Metal

Assembly code for Raspberry Pi

Raspberry-Pi Bare Metal Tutorial

uCOS-II on Raspberry Pi

Porting uCOSII to the raspberry pi A+/B+/2B

Bare-metal examples

Bare-metal lab

Exploring Raspberry Pi: Interfacing to the Real World with Embedded Linux {book}

Exploring Raspberry Pi: Interfacing to the Real World with Embedded Linux {website}

Writing a "bare metal" operating system for Raspberry Pi 4

PiSpot-Show

A Raspberry Pi captive portal that creates a WiFi hotspot displaying a customizable web page to connected users using hostapd, dnsmasq, and nginx.

BeagleBone Black I2C References

Learning BeagleBone Python Programming

Simple implementation of an OS for the BeagleBoard C4 with ARMv7 A8 processor.

Various projects that utilize low level hardware instructions to interface with leds, speaker output and joystick input.

Windows Embedded Compact BSP for TI's Beaglebone

BBB-BareMetal

Works on the beaglebone black (bare metal)

Running a Baremetal Beaglebone Black

& Part 2

Bare Metal on the BeagleBone (Black and Green)

& link1 + Link2

A tutorial on bare-metal [OS] development on the Texas Instruments BeagleBoard.

bare metal c project for beaglebone, ti sitara am335x

Bare Metal Applications on OSD335x using U-Boot

bbb-asm-demo

Extremely tiny baremetal application for BeagleBone Black

Beaglebone - Getting started with JTAG and CCS

BeagleBoardJTAG

beaglebone_samples

FreeRTOS for BeagleBone Black

Linux inside

A little bit about a linux kernel

Writing device drivers in Linux

YOLINUX Tutorials

Linux driver programming

Free training materials and conference presentations

eBook: Linux Drivers

or Slides: Linux Drivers

c-periphery

A C library for peripheral I/O (GPIO, SPI, I2C, MMIO, Serial) in Linux.

OpenEmbedded

,

Linux driver practices

Linux Kernel Exploitation

A bunch of links related to Linux kernel exploitation

Linux Kernel Module Cheat

Start linux kernel module development!

Minimal Linux Live

a tiny educational Linux distribution

How to be low-level programmer

Yocto Project

Create custom Linux-based systems regardless of the hardware architecture.

Buildroot

Simple, efficient and easy-to-use tool to generate embedded Linux systems through cross-compilation.

GCC-Inline-Assembly-HOWTO

Assembly programming

List of open source real-time operating systems

A list of open source Real Time Operating Systems (RTOS). Licence: CC BY-SA 3.0.

ROS

The Robot Operating System (ROS) is a flexible framework for writing robot software. It is a collection of tools, libraries, and conventions that aim to simplify the task of creating complex and robust robot behavior across a wide variety of robotic platforms.

FreeRTOS

is an open source, real-time operating system for microcontrollers that makes small, low-power edge devices easy to program, deploy, secure, connect, and manage.

FreeRTOS - Explanation

overiview.

FreeRTOS API Reference Documentation

How to Write a Small RTOS

RTOS From Scratch

mini-arm-os & qemu with a stm32

or here - Build a minimal multi-tasking OS kernel for ARM Cortex-M series from scratch

Writing a simple operating system from scratch

by Nick Blundell

Free real-time operating system (RTOS) designed for deeply embedded applications

MPSoC FreeRTOS Development

Atomthreads: Open Source RTOS

High performance motor control

The aim is to make it possible to use inexpensive brushless motors in high performance robotics projects.

MINIX3: Open source RTOS

Minix® is a POSIX®-compliant Unix-like computer operating system based on a microkernel architecture. In 2017 it was learned that Intel™ used a version of MINIX on many of its x86-series processors, perhaps making it the most popular Unix-like operating system .

30 Days make OS

> YOS @Yannik

Real-time System Group

object-oriented C++ RTOS for microcontrollers

Object-oriented C++ RTOS for microcontrollers.

RT-Thread is an open source IoT operating system from China.

RT-Thread was born in 2006, it is an open source, neutral, and community-based real-time operating system (RTOS). RT-Thread has Standard version and Nano version. For resource-constrained microcontroller (MCU) systems, the NANO kernel version that requires only 3KB Flash and 1.2KB RAM memory…

How to create an OS from scratch

How to create an OS from scratch

Sample Source: TetrOS is a small feature rich Tetris clone which is written in Assembly.

Sample Source: RTOS for microcontrollers

Sample Source: A Powerful embedded RTOS for ARM Cortex M microcontrollers

Sample Source: An embedded operating system for ARM Cortex-M based microcontrollers

Sample Source: rnk is a RTOS targeting ARM architecture.

Sample Source: RTOS-From-Scratch

Sample Source: Embeded OS for PIC32MX270F256B

How I ended up writing a new real-time kernel

Sample Source: TNeo - a well-formed and carefully tested preemptive real-time kernel for 16- and 32-bits MCUs

RT-Thread for Raspberry Pi 2B

tock

A secure embedded operating system for Cortex-M based microcontrollers.

AliOS-Things

AliOS Things released by Alibaba is an open-source implementation of operating system (OS) for Internet of Things (IoT).

CoRTOS

& CoRTOS Simple Cooperative RTOS - An open source minimalist RTOS.

µOS++ Reference

TNKernel

a compact and very fast real-time kernel for the embedded 32/16/8 bits microprocessors.

Femto OS

a very concise portable real time - preemptive operating system (RTOS) for embedded microcontrollers with minimal ram and flash, say 2KB .. 16KB flash and 128 .. 1024 bytes ram.

Real-Time Kernel '0'

A lean, highly deterministic, low-latency real-time kernel for ARMv6/7M.

Sample Source: Trampoline is a static RTOS for small embedded systems.

& labs

Sample source: An integration an example AUTOSAR project which every part in AUTOSAR (OS, RTE, BSW, MCAL) are…

automotive software(OSEK & AUTOSAR)

Because I am not powerful so I decided to develop tiny but smart part of automotive software based on open source, and create a general AUTOSAR & Automotive Software study environment.

BlackFlag ECU

Automotive CAN bus security testing and analysis tool for ECU research, fuzzing, and reverse engineering of vehicle communication protocols.

ucLinux

The Embedded Linux/Microcontroller project is a port of Linux to systems without a Memory Management Unit (MMU).

Tizen

Bootstrap yourself to write an OS from scratch. A book for self-learner.

Kernel 101 – Let’s write a Kernel

The little book about OS development

by Erik Helin and Adam Renberg

Sample Source: TetrOS is a small feature rich Tetris clone which is written in Assembly.

Writing a simple operating system from scratch

by Nick Blundell

JamesM's kernel development tutorials

by James Molloy

Bare Bones

a simple kernel for 32-bit x86 and boot it.

Operating System Development Series

OS from the ground up in C

7 Steps to Writing a Simple Cooperative Scheduler

A simple OS kernel for research, teaching, and fun

A simple OS kernel for research, teaching, and fun

Operating Systems C Term 2018

GuruCE Blog

Windows CE Base Team Blog

DevWinCE blog

Windows Embedded Compact BSP for Raspberry Pi

Windows Embedded Board Support Package for BeagleBone

ARM Compiler - armasm User Guide

Writing a boot loader in Assembly and C

Writing a Bootloader Part 3

A bootloader for ARM Cortex-M based microcontrollers

OpenBLT

an open source and portable bootloader for microcontrollers.

ARMv7M ELF loader

Writing a Bootloader Part 1

by Alex Parker

can-bootloader

The bootloader used to flash our CAN-connected boards

Bootloaders 101

Managing projects with GNU Make

GCC and Make

Building Hardware Components for Memory Protection of Applications on a Tiny Processor

KeyStone Architecture: Memory Protection Unit (MPU)

tinyusb

An open source USB stack for a variety of Embedded Systems.

A practical approach to Kalman filter and how to implement it

Embedded System programming

Diving into Syllabus for investigation.

ELC 2018 Presentations

ARM Edition

Sparky ARM Edition is a Sparky version created for a single board mini computer RaspberryPi.

The gem5 Simulator

is a well-known sophisticated simulator used for computer system research at both architecture and micro-architecture levels. Main page is here.

LineageOS Android Distribution

The NoCAN platform

Realtime OS on Embedded Systems

These projects were produced in the five weeks of ECE 4760 each year.

Advanced fault backtrace library for ARM Cortex-M series MCU

Advanced fault backtrace library for ARM Cortex-M series MCU | ARM Cortex-M 系列 MCU 错误追踪库

mcu-starter-projects

Simple starter projects for bare-metal MCU development.

DirtyJTAG

JTAG adapter firmware for STM32F1

Generic_MCU_Software_Infrastructure

Provide necessary software infrastructure, service, macros to support some high level abstract concept or paradigm, such as OOPC, FSM, delegate (event-driven) and etc.

apollo

An open autonomous driving platform.

A Development Environment for ARM TrustZone with GlobalPlatform Support

A C++ template library for embedded applications

Embedded Template Library where the user can declare the size, or maximum size of any object upfront.

Embedded rework of C++ STL

basic_string, basic_ostream etc. leaned way down. Cross platform (including AVR).

RAMEN 🍜

flow-based programming implemented in a simple single-header unopinionated library.

Embedded Wizard

Sophisticated GUI for Your Embedded Platform

lvgl

Graphics library to create an embedded GUI with easy-to-use graphical elements, beautiful visual effects and low memory footprint. It offers anti-aliasing, opacity, and animations using only one frame buffer.

nnom

A higher-level Neural Network library for microcontrollers.

nn4mp

Embedded Learning Library (ELL)

Microsoft's library to deploy intelligent machine-learned models onto resource constrained platforms and small single-board computers.

Qualcomm Neural Processing SDK for AI

Libraries to developers run NN models on Snapdragon mobile platforms taking advantage of the CPU, GPU and/or DSP.

CMSIS NN

A collection of efficient neural network kernels developed to maximize the performance and minimize the memory footprint of neural networks on Cortex-M processor cores.

ARM Compute Library

Set of optimized functions for image processing, computer vision, and machine learning.

uTensor

AI inference library based on mbed (an RTOS for ARM chipsets) and TensorFlow.

EmbededAI

A library that provides elements of AI to C++ applications.

kann

A lightweight C library for artificial neural networks.

m2cgen

A CLI tool which allows to transpile trained classic ML models into a native code of various programming languages with zero dependencies including C.

nn2

Tiny zero-dependency neural network inference engine in pure C with hand-written SIMD kernels (AVX-512 / AVX2 / NEON). Runs the FaceX face recognition stack on Apple Silicon, ARM SBCs and ESP32-P4. Apache 2.0.

edge-agents (ForestHub)

Open-source (AGPL-3.0) 30 MB AI agent runtime for edge devices. Offline by default; GPIO/UART/MQTT as first-class nodes; local SLMs alongside cloud LLMs. Runs on Raspberry Pi 5, Jetson Orin Nano, STM32MP25, ctrlX CORE.

TiGrIS

Ahead-of-time compiler that tiles ONNX models to fit microcontrollers with fixed RAM and flash budgets, executed by a dependency-free C runtime.

voicute

Lightweight keyword spotting and wake word detection engine for ESP32 with INT8 quantization (~74KB per keyword), multi-language support including Chinese, and cross-platform ONNX Runtime inference.

Jumpstarter

Open source hardware-in-the-loop testing framework for automated testing on real and virtual embedded hardware with CI/CD integration.

flashgate

Hardware-in-the-loop verification gate for AI coding agents: build, flash over ST-Link, then assert the board's boot banner, SWD RAM signature and console-probe register readbacks before "done" is accepted. Ships as a Claude Code plugin (Stop hook + MCP server).

lm4tools

EmbedEval

Benchmark that measures how well LLMs write embedded firmware. 233 cases across Zephyr, ESP-IDF, STM32 HAL, FreeRTOS, Linux drivers and Yocto, verified through static checks, SDK compilation, runtime execution and mutation testing.

mspdebug

Debugging tool for MSP430 MCUs

pycs

Python Based ARM CoreSight Debug and Trace Tools

NaiveSystems Analyze

Static Analysis Tool for Code Security and Compliance

CRA Kit SBOM

Zero-dependency CI script that reads Zephyr, Yocto, Buildroot, PlatformIO, ESP-IDF and STM32Cube build manifests and emits CycloneDX SBOMs.

Serial Studio

Visualize, analyze and stream over the internet data generated by your MCU project

Scrutiny Debugger

An open source debugging, visualization and testing tool for C/C++ embedded applications that works through instrumentation.

MemBrowse

Memory footprint tracking for ELF binaries with CLI and CI integration to monitor flash/RAM usage across commits.

aem-modbus-simulator

Open-source Python Modbus RTU/TCP slave simulator emulating an industrial DC voltage monitor (147 holding registers, 6 baudrates). Lets SCADA/PLC firmware engineers test Modbus integration in CI pipelines without physical hardware on the bench.

memprobe.dev

ELF firmware analysis as a web app, CLI, and GitHub Action. Break down flash and RAM usage by section, file, library, and symbol, compare builds, track project history and memory growth over time, and set CI size budgets.

SiliconRig

Cloud-hosted embedded boards (ESP32-S3, STM32, RP2350) for remote flashing, serial console, and hardware-in-the-loop testing in CI. Open-source CLI, Python SDK, and GitHub Action.

Velxio

Fully local, open source Arduino simulator with real AVR8, RP2040 and ESP32 emulation, a visual circuit canvas and an in-browser code editor. Runs in the browser or self-hosted via Docker.

BARR-C Enforcement Kit

Drop-in clang-format and clang-tidy configurations, compiler warning gates, a one-command conformance check and ready-made CI enforcing BARR-C, Barr Group's Embedded C Coding Standard for firmware.

Awesome Cheat Sheets

Vim Config for Reading Linux Kernel Source Code

GNU GDB Debugger Command Cheat Sheet

What a C programmer should know about memory

What Every Programmer Should Know About Memory

by Ulrich Drepper [pdf]

What Every C Programmer Should Know About Undefined Behavior

part 2 part 3

A Guide to Undefined Behavior in C and C++

Software Engineering Takeaways

Embedsys weekly newsletter

. A weekly selection of embedded software and hardware articles.

EdgeLog

Embedded and edge AI engineering notes, with measurements from running LLMs and agents against real hardware.

Boot section is removed (gcc, ld, ar, as)

What are .axf files?

awesome-c

A curated list of awesome C frameworks, libraries and software.

A curated list of project-based tutorials in C

Curated list of project-based tutorials

Programming tutorials to build an application from scratch.

Curated list of awesome lists

A list of SaaS, PaaS and IaaS offerings that have free tiers of interest to devops and infradev

A curated list of awesome Raspberry Pi tools, projects, images and resources

by @thibmaek – Raspberry Pi tools, projects, images and resources

Curated List of Self-Driving Cars and Autonomous Vehicles Resources

awesome-embedded-systems

Awesome list of embedded programming resources.

Awesome Cheat Sheets

awesome-embedded-rust

Curated list of resources for Embedded and Low-level development in the Rust programming language.

theEmbeddedNewTestament.github.io

Mastering the Raspberry Pi

Modern C

An Embedded Software Primer

Embedded Software with Rust

A practical introduction to building firmware that is fast, efficient, and far safer than traditional embedded software written in C or C++.