Adding ADC to Microcontrollers without ADC

Scott Harden writes: I recently had the need to carefully measure a voltage with a microcontroller which lacks an analog-to-digital converter (ADC), and I hacked together a quick and dirty method to do just this using a comparator, two transistors, and a few passives. The purpose of this project is to make a crystal oven […]

VHF Frequency Counter with PC Interface

Scott has published a new build: This is the general idea behind how this frequency counter works. It’s so simple! It’s entirely digital, and needs very few passive components. sn74lv8154 is configured in 32-bit mode (by chaining together its two 16-bit counters, see the datasheet for details) and acts as the front-end directly taking in […]

Controlling Bus Pirate with Python

Scott W Harden writes, “After using the AVR-ISP mkII for years (actually the cheap eBay knock-offs) to program ATMEL AVR microcontrollers, today I gave the Bus Pirate a shot. Far more than just a microcontroller programmer, this little board is basically a serial interface to basic microcontroller peripherals.” Full details at SWHarden homepage. Get your own handy […]

Pressure, temperature and humidity sensor based on MS5637 HDC1080

Mare writes: This is another small module to measure air pressure, temperature and humidity. Two sensors are on-board: MS5637 and HDC1080. Microcontroller is small cortex M0 in TSSOP-20 housing from STM: STM32F070CxP. The SN65HVD72DGKR provides RS485 interface functionality with half duplex mode. Voltage regulator, reverse polarity protection and some LED indicators are provided on-board. Complete […]

Programmable CW Morse Keyer / beacon

Marko Pavlin has designed a Mini USB dongle with STM32F0xx , he writes: Mini USB dongle with STM32F0xx is suitable many for simple, mini projects. I attached speaker to Timer14 PWM output (Pin PA6) and LED (or optocoupler connected to PTT) to GPIO pin PA0 The provided software is based on USB Virtual Com Port (VCP) device. […]

Atmega16u2 virtual serial example using LUFA Library

Shane of Wattnotions has published a new build, an Atmega16u2 virtual serial LUFA board: What I wanted the LUFA library to do was pretty specific – the atmega16u2 should show up as a virtual serial port so that the computer can connect and read data from it like any other serial port. All of the other […]

STM32 Nucleo and DFU USB bootloading

MrMobileWill writes: Over the last few months I have been playing with the Nucleo development boards from STMicroelectronics. If you’re unfamiliar with them, they are fast, mbed and Arduino (headers) compatible. This makes it easy like an Arduino to program and use. What sets them apart is that they are 32bit and have, depending on […]

A GUI and CLI utility for EFM32’s UART bootloader

Mario writes: I’ve been doing mostly sensor-based systems and I think these microcontrollers are the perfect fit. ARM Cortex (they go from M0 to M4, and their series seem to keep growing), an architecture that was specially designed for low-power sensor-based embedded systems, allowing to measure “stuff” while the CPU is stopped, a nice set […]

XMega analog comparator

Shawon Shahryiar over at Embedded Lab has written an article on XMega analog comparator: Generally a comparator is a device that compares two quantities. Analog comparators compare voltage – an analog quantity. An analog comparator is essentially an op-amp with infinite gain. It has one output and two inputs. The output is switched to VDD […]

Designing a PIC24 development board

Brian Dorey has designed and built a PIC24 development board, that is available at GitHub: One problem we found was trying to prototype code using this microcontroller as unlike Arduino and any ARM microcontrollers there isn’t a small easy to use prototyping board available for the PIC24 chip.  Microchip make an Explorer 16 Development Board which […]

iButtonLink T-Sense 1-wire sensor (Maxim DS18B20) + PIC 18F14K22

Chas over at PNW/Electronics writes: I came across a stash of iButton T-sense 1-wire sensors.. so I grabbed a couple and decided to check out 1-wire. Maxim makes a 1-wire device called the DS18B20. It’s a 9-12 bit temperature sensor with the possibility of being powered by parasitic power from the data line. This cuts […]

ATXMega Primer

Shawon Shahryiar over at Embedded Lab talks about Atmel XMega in this tutorial: At present we have different families of XMega devices. Of these many we are focused toward the AU series only throughout this post and its following ones. I’ll explain later why I’m interested in this series. This is the first post of a series of posts […]

Power line communication

Haris Andrianakis wrote a post on his blog detailing his power line communication system: The main purpose was to implement two devices communicating each other, using the technology of power line. Specifically, at this project the communication has been used to send data from a weight bridge/ weight machine to a remote display. For the power line communication has […]

Oscillator controller for 8bit PIC microcontrollers

Dilshan Jayakody writes: This is oscillator controller for 8bit PIC microcontrollers which is specifically design to debug MCUs and related circuits by without using ICD unit. This unit consists with low speed oscillator and cycle counter with automatic hold. In current version, oscillator is capable to run in 2 frequency modes and it can count […]