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 […]

An AVR Atmega library for multiple HD44780 based LCD connected through i2c

Davide Gironi has posted an I2C multiple HD44780 AVR Atmega library: This library implements a driver for HD44780 lcd connected through PCF8574 port expander. Data is transmitted using only 2 wire over i2c with the PCF8574. This library can drive up to 8 LCD concurrently. Lcd driver is based upon Peter Fleury’s lcd driver HD44780 […]

ATtiny based bidirectional motor control using L293D

Rahul over at Xanthium has posted a tutorial on interfacing ATtiny with L293D: In this tutorial we will learn to interface L293D with ATMEL ATtiny microcontroller and control them bidirectionally.The microcontroller used here is ATtiny2313A which is interfaced to two L293D motor control chips for controlling upto 4 DC brushed motors.You can control upto 8 […]

Touchpad as wireless (MIDI) expression controller

Acidbourbon has published a new build, a wireless touchpad that can be used like an expression pedal: This sort of touchpad speaks some special Apple mouse protocol. Luckily I found a code snippet on mikrocontroller.net which helped a great deal to get the thing going. Then I used a standard AVR ATMega8 microcontroller to glue […]

AC energy metering board using an Atmel 90E24 energy metering chip

Steve Rodgers writes, “Here’s my latest project.  Its an AC energy metering board using an Atmel 90E24 energy metering chip. The board can either take an ESP8266-12 and run a native C application, or the ESP8266-12 can be omitted, and an external microcontroller can be used to talk to the Atmel 90E24 energy metering chip. […]

AMQUMO: A Xively AMbient QUality MOnitor built on ATmega328

Davide Gironi published a new build, AMQUMO -an ATmega328 AMbient QUality MOnitor: AMQUMO logs 4 environmental parameters: -Humidity -Temperature -Ambient Noise -Brightness The data it is logged to the xively.com platform, and displayed to the user through 4 bi-color leds. It can be used to monitor you Office Ambient Quality over the parameters logged. This project […]

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 […]

ChipHeadBang – design for an USB to Serial converter with ICSP header for (slow) bitbang programming

microtherion has published new project the ChipHeadBang, that is available on Github: Design for an USB to Serial converter with ICSP header for (slow) bitbang programming, based on the CH340G chip. While this seems to work pretty well, and the CH340G can be obtained extremely cheaply from sources such as AliExpress, driver support can be a bit […]

Drive an old laptop display from an AVR

Jean refers us to this article by Eric Wazhung  about interfacing LVDS displays using an 8-bit AVR: Different displays have different (undocumented) functionality. With the several I’ve tested, I’ve attempted to create a step-by-step procedure to get a new display going (or find out early-on if it’s not possible. So far I haven’t run into one that […]

AVR-HV: High voltage programmer for AVR microcontrollers

Dilshan Jayakody writes:  AVR-HV is high voltage parallel programmer for Atmel AVR series microcontrollers. AVR-HV allows programming, reading, verifying and configuring AVR microcontrollers with its high voltage programming interface and it connected to PC using USB interface. In High voltage programming mode, 12V programming voltage is applied to RESET pin of target AVR microcontroller and in […]

Drive a stepper motor with acceleration and deceleration using an Allegro driver on ATmega8

Davide Gironi writes: This library drive a stepper motor using the Allegro A3967 (EasyDriver) on ATmega8. It will also work on the Allegro a4988, and other type of motor driver controlled by the number of pulse received. It features: direction changing speed changing acceleration and deceleration multiple motor driving stop spinning after number of step, […]