GNU Linker Scripts. Part 1. .data, .bss, and the Startup Contract
Before your first line of C code executes, your system must establish a vital memory contract. Discover how the GNU Linker manages the transition from power-on to a ready-to-run state by deconstructing the roles of .data and .bss sections. Learn how to map Virtual and Load Memory Addresses effectively and decode the startup routines that initialize your global variables. By mastering these fundamental linker script mechanics, you gain total control over your embedded application's memory layout and ensure your startup code performs reliably every time.
Project Log: Pixelblaze Christmas Lights
Festive fun and the hacker spirit combine in my janky attempt to adorn my house with addressable LEDs! In this post, I show you how I used a Pixelblaze and a cheap strip of WS2811 RGB LEDs (and not a little bit of hot glue and paper clips) to make a super cool set of Christmas lights.
How to Design Reliable Reset Circuits for Embedded Microcontrollers
In the world of embedded systems, the reset circuit is a critical component that ensures the microcontroller starts up correctly and recovers gracefully from unexpected events like power fluctuations or software crashes. A poorly designed reset circuit can lead to erratic behavior, system lockups, or even permanent damage to the microcontroller. For embedded engineers, designing a reliable reset circuit is essential for ensuring the stability and robustness of the system.
Working with Microchip PIC 8-bit Interrupts
This fifth and final post of the Getting Started with Microchip PIC 8 Bit Development series looks at interrupts on 8-bit PIC microcontrollers. After a review of basic interrupt functionality, an actual implementation is explored with the development of a four bit counter driven via Timer0 interrupts whose value is displayed through four LEDs on Microchip's Curiosity HPC Development Board.
Hidden Gems from the Embedded Online Conference Archives - Part 2
A look back at a deep dive into the Mars Perseverance flight software from one of the technical leads at JPL.
On hardware state machines: How to write a simple MAC controller using the RP2040 PIOs
Hardware state machines are nice, and the RP2040 has two blocks with up to four machines each. Their instruction set is limited, but powerful, and they can execute an instruction per cycle, pushing and popping from their FIFOs and shifting bytes in and out. The Raspberry Pi Pico does not have an Ethernet connection, but there are many PHY boards available… take a LAN8720 board and connect it to the Pico; you’re done. The firmware ? Introducing Mongoose…
Picowoose: The Raspberry Pi Pico-W meets Mongoose
This example application describes the way to adapt the George Robotics CYW43 driver, present in the Pico-SDK, to work with Cesanta's Mongoose. We are then able to use Mongoose internal TCP/IP stack (with TLS 1.3), instead of lwIP (and MbedTLS).
How to use analog input (ADC) on NuttX RTOS
Hands-on walkthrough showing how to read analog voltages on a Raspberry Pi Pico running NuttX RTOS. The post explains RP2040 ADC basics, which GPIO channels and the internal temperature sensor are exposed, and how rp2040_adc_setup creates /dev/adc0. It also shows the menuconfig options, build and UF2 flash steps, a simple potentiometer test, and a note about RP2040 ADC spike artifacts.
My friend, the compiler
Modern compilers were given great powers, but we don't always know where and when they'll use them. This may cause us to either worry needlessly or trust unjustifiably, as demonstrated by a little example in this post.
Stand-by or boot-up
Many factors affect the usability of devices - a key one is how long it takes to start up.
VHDL tutorial
Gene Breniman presents a hands-on VHDL walkthrough for a programmable clock divider implemented on a Xilinx CoolRunner CPLD (XC2C32A). The example shows how to declare ports and internal signals, implement a clock-division process with reset and falling-edge detection, and create a simple addressable latch to select clock rates from a 40MHz master clock. It’s a compact, practical guide for embedded engineers learning VHDL and CPLD design.
Memory Mapped I/O in C
Interacting with memory mapped device registers is at the base of all embedded development. Let's explore what tools the C language - standard of the industry - provide the developer with to face this task.
Introduction to Microcontrollers - Beginnings
Mike Silva's beginner tutorial series walks through core microcontroller concepts and practical steps to get started, from wiring an LED blinky to understanding startup code. He compares embedded and desktop programming, explains why C and assembly matter, and introduces AVR and STM32 Cortex-M3 toolchains and hardware. Expect clear examples, no-nonsense tool advice, and the essential hardware knowledge to move from simulator to a real board.
Chebyshev Approximation and How It Can Help You Save Money, Win Friends, and Influence People
Are expensive math libraries or huge lookup tables eating CPU and flash on your microcontroller? In this practical guide Jason Sachs shows how Chebyshev polynomial approximation (with range reduction, splitting, and small interpolated tables) can give near-minimax accuracy while using far less code and runtime. The post compares Taylor series, plain and interpolated tables, and explains how to fit empirical sensor data and evaluate coefficients efficiently.
Introduction to Microcontrollers - Interrupts
Interrupts are not magic, they are the practical tool that lets a microcontroller respond in microseconds while still doing background work. This introduction explains what an interrupt and an ISR are, how return addresses and CPU state are saved, and why ISRs must be short and carefully written. AVR and STM32 external-interrupt examples show real configuration steps and key gotchas to watch for.
You Don't Need an RTOS (Part 2)
In this second article, we'll tweak the simple superloop in three critical ways that will improve it's worst-case response time (WCRT) to be nearly as good as a preemptive RTOS ("real-time operating system"). We'll do this by adding task priorities, interrupts, and finite state machines. Additionally, we'll discuss how to incorporate a sleep mode when there's no work to be done and I'll also share with you a different variation on the superloop that can help schedule even the toughest of task sets.
7 Essential Steps for Reducing Power Consumption in Embedded Devices
Reducing the amount of power your embedded device is consuming is not trivial. With so many devices moving to battery operations today, maximizing battery life can be the difference between a happy, raving customer and an unhappy one that ruins your company's reputation. This post explores seven steps for optimizing your embedded systems' power consumption. You'll gain insights into the steps and techniques necessary along with receiving a few resources to help you on your journey.
Visual Studio Code Extensions for Embedded Software Development
Visual Studio Code can be a solid embedded development environment, if you equip it with the right extensions. Jacob Beningo walks through tools for Cortex-M debugging, register and RTOS inspection, build system support, formatting, linting, and vendor-specific workflows. It is a practical tour of the extensions that help VS Code feel much less like a general-purpose editor and more like an embedded IDE.
Introduction to Microcontrollers - Timers
Time is everything in embedded systems, and Mike Silva walks through how microcontroller timers turn clock pulses into dependable events. He covers prescalers, counter bit widths, overflow versus compare modes, atomic multi-byte register access, the "-1 rule", input capture and compare leapfrogging, with concrete AVR and STM32 code that highlights common pitfalls and reliable patterns for precise ticks.
Using the Beaglebone PRU to achieve realtime at low cost
Fabien Le Mentec shows how the BeagleBone Black's PRU coprocessors can run hard realtime control loops, removing the need for an FPGA or dedicated microcontroller. He walks through Linux setup, device tree enabling, assembler and loader tools, and a timer example that reads ADCs and drives PWM from PRU code. The post highlights community SDKs and a recent TI Code Composer Studio option for C-based PRU development.
Introduction to Microcontrollers - Beginnings
Mike Silva's beginner tutorial series walks through core microcontroller concepts and practical steps to get started, from wiring an LED blinky to understanding startup code. He compares embedded and desktop programming, explains why C and assembly matter, and introduces AVR and STM32 Cortex-M3 toolchains and hardware. Expect clear examples, no-nonsense tool advice, and the essential hardware knowledge to move from simulator to a real board.
MSP430 Launchpad Tutorial - Part 2 - Interrupts and timers
Interrupts let the MSP430 respond to events without wasting CPU time, and this tutorial walks through using TimerA and Port 1 interrupts on the LaunchPad. Enrico shows how to configure TACTL, CCR0 and CCTL0 to generate a periodic TimerA interrupt, and how to set up P1IE, P1IES and P1IFG to catch a button press. The code toggles LEDs and enters LPM0 while waiting for interrupts.
Chebyshev Approximation and How It Can Help You Save Money, Win Friends, and Influence People
Are expensive math libraries or huge lookup tables eating CPU and flash on your microcontroller? In this practical guide Jason Sachs shows how Chebyshev polynomial approximation (with range reduction, splitting, and small interpolated tables) can give near-minimax accuracy while using far less code and runtime. The post compares Taylor series, plain and interpolated tables, and explains how to fit empirical sensor data and evaluate coefficients efficiently.
MSP430 LaunchPad Tutorial - Part 4 - UART Transmission
Want to stream sensor or debug data from an MSP430 LaunchPad to a PC or Bluetooth module? Enrico swaps in an MSP430G2553 and shows how to configure SMCLK, P1 pin multiplexing, and UCA0 baud/dividers (with modulation) to approximate 115200 baud. The post also walks through interrupt-driven RX/TX handling and a low-power wait loop that sends a "Hello World" reply on demand.
MSP430 Launchpad Tutorial - Part 1 - Basics
A working button-driven LED on the MSP430 LaunchPad is only a few steps away. Enrico Garante walks through creating a CCS project, setting P1.0 as the LED output and enabling P1.3 button interrupts, then shows the interrupt service routine that toggles the LED. The short tutorial covers stopping the watchdog, configuring P1DIR/P1OUT, clearing flags, and launching the code so you can get blinking quickly.
How to Estimate Encoder Velocity Without Making Stupid Mistakes: Part I
Encoder velocity estimation is easy to get wrong, and Jason Sachs walks through the traps engineers fall into. He demolishes the common advice to time between encoder edges, shows how encoder quantization and state-width errors break that approach, and argues for fixed-rate sampling with sensible filtering for most control uses. Part II will cover more advanced estimators for higher performance needs.
Using the Beaglebone PRU to achieve realtime at low cost
Fabien Le Mentec shows how the BeagleBone Black's PRU coprocessors can run hard realtime control loops, removing the need for an FPGA or dedicated microcontroller. He walks through Linux setup, device tree enabling, assembler and loader tools, and a timer example that reads ADCs and drives PWM from PRU code. The post highlights community SDKs and a recent TI Code Composer Studio option for C-based PRU development.
Introduction to Microcontrollers - Driving WS2812 RGB LEDs
Mike Silva walks through a practical, cycle-counted AVR assembly implementation to bit-bang WS2812B RGB LEDs from an 8MHz AVR, hitting the chip's tight 1.25µs-per-bit timing. The post breaks down the WS2812B self-clocked protocol and GRB byte order, explains register and calling-convention choices, and includes a complete C example plus power-consumption warnings for driving LED strips.
Introduction to Microcontrollers - Interrupts
Interrupts are not magic, they are the practical tool that lets a microcontroller respond in microseconds while still doing background work. This introduction explains what an interrupt and an ISR are, how return addresses and CPU state are saved, and why ISRs must be short and carefully written. AVR and STM32 external-interrupt examples show real configuration steps and key gotchas to watch for.
VHDL tutorial
Gene Breniman presents a hands-on VHDL walkthrough for a programmable clock divider implemented on a Xilinx CoolRunner CPLD (XC2C32A). The example shows how to declare ports and internal signals, implement a clock-division process with reset and falling-edge detection, and create a simple addressable latch to select clock rates from a 40MHz master clock. It’s a compact, practical guide for embedded engineers learning VHDL and CPLD design.
