Category Archives: AVR

μSim: PICmicro instruction simulator

Dilshan has published a new build: μSim is a lightweight PIC™ CPU and ALU simulator. This simulator supports the PICmicro mid-range instruction set and designed to work on both PC and Arduino platforms. Compare with most of the other emulators, μSim does not provide all MCU features and peripherals. This simulator design as a minimalistic […]

High-voltage FLASH programming on ATTINY85

ATTINY85 High-Voltage Flash programmer @ td0g.ca: The Atmel ATTINY85 is a great chip (cheap, easy to use, supported in the Arduino IDE). Unfortunately it only has 5 IO pins, which limits its usability. There are guides on using a High-Voltage Programmer (HVP) to change the Reset pin into an IO pin. However, that prevents you […]

MCP4141 based digital potentiometer

Dilshan Jayakody has been working on an open-source hardware project MCP4141 based digital potentiometer, that is available on GitHub: The main objective of this project is to create an experimental prototype of a digital potentiometer using Microchip’s MCP4141 IC. MCP4141 is available with end-to-end resistances of 5KΩ, 10KΩ, 50kΩ, and 100KΩ. This potentiometer-module can drive […]

AVR high voltage programmer 2

Dilshan Jayakody posted an update on his AVR high voltage programmer project we covered previously: AVR-HV2 is Arduino based high voltage parallel programmer for AVR microcontrollers. This programmer can read, write, and erase both flash memory and EEPROM. Also, this can use to set fuse bits of AVR MCUs. Compare with the previous version of […]

Building a better bit-bang UART – picoUART

Ralph Doncaster writes, ” The screen shot above is from picoUART running on an ATtiny13, at a baud rate of 230.4kbps. The new UART has several improvements over my old code. To understand the improvements, it helps to understand how an asynchronous serial TTL UART works first. Most embedded systems use 81N communication, which means […]

An ATmega brushless sensored motor driver v02

David Gironi writes, “Brushless electric motor (BLDC motors) are synchronous motors that are powered by a DC electric source via an integrated inverter/switching power supply, which produces an AC electric signal to drive the motor. Hall sensored motors uses hall effect sensors or a rotary encoder to directly measure the rotor’s position. See the full […]

An ATmega brushless sensorless motor driver v02

Davide Gironi has posted an update on his ATmega brushless sensorless motor driver project we covered previously: Brushless electric motor (BLDC motors) are synchronous motors that are powered by a DC electric source via an integrated inverter/switching power supply, which produces an AC electric signal to drive the motor. See the full post on his […]

Drive an MCP49XX series DAC with an AVR ATmega

Davide Gironi writes: Driving that IC is pretty simple, expecially if you have a dedicated SPI hardware interface, like many microchip has. The ATmega8, used in this example has a dedicated SPI Control Register (SPSR) that one can use to setup the SPI interface. This library can drive more then one MCP49XX of the same […]

Nano current meter based on an ATtiny84

Johnson Davies published a new build: This project describes a simple low-current meter I devised to check the sleep current of different microcontroller circuits, such as ones based on AVR microcontrollers. It’s capable of measuring currents of between 10µA and 30nA with reasonable accuracy, using an ATtiny84 and a few other low-cost parts Project details […]

ATTiny85 Pulse oximeter with photoplethysmogram (PPG) display

tinyPulsePPG, an ATTiny85 Pulse Oximeter with Photoplethysmogram (PPG) display by Jeff Magee: This project implemented on an ATTiny85 displays a moving Photoplethysmogram together with pulse rate and estimates of SpO2 – blood oxygen percentage. It uses an SSD1306 128×32 OLED display and a Max30102 sensor. It is emphasised that this should not be used for […]

FM stereo radio receiver with RDS

Dilshan Jayakody has published a new build: This tuner circuit is a quick prototype which I build to test the RDA5807M FM radio tuner IC. RDA5807M is a single-chip tuner IC with RDS and MPX decoder, and it equipped with I2C interface for control. This receiver builds around Atmel’s ATmega16A 8-bit MCU. The output stage […]

HX711 load cell amplifier library for AVR ATmega

A HX711 load cell library for AVR ATmega: HX711 is a precision 24bit ADC IC designed for weigh scales and industrial control applications to interface directly with a bridge sensor. A load cell is a transducer that is used to create an electrical signal whose magnitude is directly proportional to the force being measured. The […]