Hidden Gems from the Embedded Online Conference Archives - Part 1
Discussion of a "hidden gem" from the Embedded Online Conference archives!
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…
How 5G impacts future IoT development
The Internet of Things (IoT) applications are ubiquitous today. IoT is used in almost every industrial, commercial, and consumer market segment, including autonomous driving, smart factories, automation and preventive maintenance, smart homes, smart cities, security, asset tracking, supply chain management, agriculture, farming, healthcare, smart medicine and remote surgery, augmented reality applications, activity monitoring, and more. The three most promising uses of IoT are smart manufacturing, autonomous driving, and healthcare, particularly remote surgery.
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).
Understanding Yocto Project Layers: A Modular Approach to Embedded Systems Development
Managing metadata across embedded Linux builds gets messy fast, so the Yocto Project uses layers to keep things modular and reusable. This post walks through inspecting active layers with bitbake-layers, controlling overrides with BBFILE_PRIORITY, and creating a meta-yocto-splash-img layer that uses a .bbappend to replace psplash. It finishes by showing how to verify the custom splash screen in QEMU so you can test safely before deploying to hardware.
Lost Secrets of the H-Bridge, Part V: Gate Drives for Dummies
Learn the most important issues in power MOSFET and IGBT gate drives: - Transistor behavior during switching - Calculating turn-on and turn-off times - Passive components used between gate drive IC and transistor - Reverse recovery - Capacitively-coupled spurious turn-on - Factors that influence a good choice of turn-on and turn-off times - Gate drive supply voltage management - Bootstrap gate drives - Design issues impacting reliability
When a Mongoose met a MicroPython, part II
In the first part of this blog, we introduced this little framework to integrate MicroPython and Cesanta's Mongoose; where Mongoose runs when called by MicroPython and is able to run Python functions as callbacks for the events you decide in your event handler. Now we add MQTT to the equation, so we can subscribe to topics and publish messages right from MicroPython.
Five Embedded Linux Topics for Newbies !
Are you an embedded systems enthusiast looking to broaden your horizons with embedded Linux? explore those 5 topics.
When a Mongoose met a MicroPython, part I
This is more a framework than an actual application, with it you can integrate MicroPython and Cesanta's Mongoose.
Mongoose runs when called by MicroPython and is able to run Python functions as callbacks for the events you decide in your event handler. The code is completely written in C, except for the example Python callback functions, of course. To try it, you can just build this example on a Linux machine, and, with just a small tweak, you can also run it on any ESP32 board.
Finite State Machines (FSM) in Embedded Systems (Part 1) - There's a State in This Machine!
An introduction to state machines and their implementation. Working from an intuitive definition of the state machine concept, we will start with a straightforward implementation then we evolve it into a more robust and engineered solution.
Lost Secrets of the H-Bridge, Part V: Gate Drives for Dummies
Learn the most important issues in power MOSFET and IGBT gate drives: - Transistor behavior during switching - Calculating turn-on and turn-off times - Passive components used between gate drive IC and transistor - Reverse recovery - Capacitively-coupled spurious turn-on - Factors that influence a good choice of turn-on and turn-off times - Gate drive supply voltage management - Bootstrap gate drives - Design issues impacting reliability
Cracking the (embedded) Coding Interview
Landing your first embedded job is thrilling, but surviving months of interviews is brutal. This post condenses one engineer’s recent experience into a pragmatic playbook, covering behavioral prep, targeted coding practice, and the embedded theory you actually get asked about. Read it for a focused roadmap: what to study, which platforms to use, and how to present yourself so interviewers root for you.
Understanding and Preventing Overflow (I Had Too Much to Add Last Night)
Integer overflow is stealthier than you think, and in embedded systems it can break control loops or corrupt data. Jason Sachs walks through the usual culprits, including addition, subtraction, multiplication, shifting and Q15 fixed-point traps, plus C-specific pitfalls such as undefined signed overflow and INT_MIN edge cases. He then lays out practical defenses: prefer fixed-width types, widen and saturate intermediates, enable wraparound where appropriate, and reason about modular congruence for compound arithmetic.
Finite State Machines (FSM) in Embedded Systems (Part 1) - There's a State in This Machine!
An introduction to state machines and their implementation. Working from an intuitive definition of the state machine concept, we will start with a straightforward implementation then we evolve it into a more robust and engineered solution.
How to Read a Power MOSFET Datasheet
Jason Sachs takes a soapbox to stop a recurring mistake: misreading power MOSFET datasheets. This practical guide separates marketing blurbs and typical graphs from the specifications you can actually rely on, and explains how to use RDS(on), VGS, gate charge, SOA and thermal data in real designs. Read this before you pick a MOSFET or size a gate driver.
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.
Thermistor signal conditioning: Dos and Don'ts, Tips and Tricks
Jason Sachs shows how to keep thermistor conditioning simple and accurate for embedded systems. He warns against analog linearization and excessive analog stages, and explains why ratiometric dividers, proper ADC buffering, and using the same reference voltage give better results. The post also covers thermal pitfalls like self-heating and lead conduction, plus practical tips for ADC autocalibration and polynomial temperature conversion.
VHDL tutorial - A practical example - part 2 - VHDL coding
Gene Breniman walks through the VHDL coding for a CPLD-based data acquisition engine, turning the hardware spec into a working state machine and signal generators. The article explains SPI and I2S timing choices, an internal SPI peripheral latch, and counter-based timing (seqCount and CycleCnt) used to create LRCK, BCK, SPI SCK and nvSRAM write control. It’s a practical, implementation-focused guide for embedded designers.
VHDL tutorial - A practical example - part 3 - VHDL testbench
Gene Breniman walks a complete VHDL testbench workflow for a CPLD-based data acquisition engine, from Xilinx ISE testbench generation to stimulus processes. He shows clock and SPI gating, a simulated ADC data generator tied to ADC_LRCK and ADC_BCK, and how simulation revealed a timing bug in the nvSRAM header that was then fixed in the VHDL. Practical and hands-on for verification work.
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.
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.
VHDL tutorial - A practical example - part 3 - VHDL testbench
Gene Breniman walks a complete VHDL testbench workflow for a CPLD-based data acquisition engine, from Xilinx ISE testbench generation to stimulus processes. He shows clock and SPI gating, a simulated ADC data generator tied to ADC_LRCK and ADC_BCK, and how simulation revealed a timing bug in the nvSRAM header that was then fixed in the VHDL. Practical and hands-on for verification work.
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.
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.
How to Read a Power MOSFET Datasheet
Jason Sachs takes a soapbox to stop a recurring mistake: misreading power MOSFET datasheets. This practical guide separates marketing blurbs and typical graphs from the specifications you can actually rely on, and explains how to use RDS(on), VGS, gate charge, SOA and thermal data in real designs. Read this before you pick a MOSFET or size a gate driver.
Understanding and Preventing Overflow (I Had Too Much to Add Last Night)
Integer overflow is stealthier than you think, and in embedded systems it can break control loops or corrupt data. Jason Sachs walks through the usual culprits, including addition, subtraction, multiplication, shifting and Q15 fixed-point traps, plus C-specific pitfalls such as undefined signed overflow and INT_MIN edge cases. He then lays out practical defenses: prefer fixed-width types, widen and saturate intermediates, enable wraparound where appropriate, and reason about modular congruence for compound arithmetic.
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.
Thermistor signal conditioning: Dos and Don'ts, Tips and Tricks
Jason Sachs shows how to keep thermistor conditioning simple and accurate for embedded systems. He warns against analog linearization and excessive analog stages, and explains why ratiometric dividers, proper ADC buffering, and using the same reference voltage give better results. The post also covers thermal pitfalls like self-heating and lead conduction, plus practical tips for ADC autocalibration and polynomial temperature conversion.
VHDL tutorial - part 2 - Testbench
In this follow-up Gene Breniman builds a VHDL testbench in Xilinx ISE, showing how to generate a continuous master clock, apply a power-on reset, and sequence register strobes to change clock divisors. He walks through timing waits and observation delays needed to verify ADC clock rates. The article also shows how simulation exposed a copy-paste bug in the original design.
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.
