RuuviTag – Open-Source Bluetooth Sensor Beacon

Open-source sensor beacon platform designed especially for makers, developers and IoT companies. Some of the features are:

  • Easy to use
  • IoT and Bluetooth 5 ready
  • Filled with sensors (it can work as a weather station!)
  • Affordable
  • Attractive design
  • and last but not least — 100% Open-Source.

A year ago we started a design process with one goal: to create a superior open-source sensor beacon platform to fulfill the needs of developersmakers, hobbyists, students and even IoT companies and normal people. We managed to create one of the most advanced Bluetooth sensor products in the world.

RuuviTag – Open-Source Bluetooth Sensor Beacon – [Link]

Dark Sensitive Switch – LED Light


Dark activated LED light is a simple project which operates a LED when the light falling on the LDR goes below a set point.  The circuit is built using LM393 comparator, LDR as light sensor, preset (potentiometer) for sensitivity adjustment, transistor to drive the LED. The project can also be considered for use in energy saving application.


  • Input – 12 V @ 1A
  • LED 12V 500mA Maximum (6W)
  • Onboard Preset for Level Adjust
  • Operation LED Indicator
  • On Board Power LED
  • Header Connector for Power Supply and LED
  • PCB dimensions 55.45MM X 12.70 MM

Dark Sensitive Switch – LED Light – [Link]


Magnetic Field Measurement Using HMC5883 and Arduino Nano


In this tutorial we are going to learn the detailed working of HMC5883 with arduino nano.

The HMC5883is a digital compass designed for low-field magnetic sensing.This device has a wide magnetic field range of +/-8 Oe, and an output rate of 160 Hz. The HMC5883 sensor includes automatic degaussing strap drivers, offset cancellation, and a 12-bit ADC that enables 1° to 2° compass heading accuracy. All I²C Mini Modules are designed to operate at 5VDC.

Magnetic Field Measurement Using HMC5883 and Arduino Nano – [Link]

How to Scroll a single LCD line – Arduino

R Jordan Kreindler show us how to scroll a single line on a LCD display.

The Liquid Crystal Library has two quite useful functions scrollDisplayLeft() and scrollDisplayRight(). These functions scroll the whole display. That is, they scroll both lines on a 1602 LCD and all four lines on a 2004 LCD. What we often need is the ability to scroll a single line on these displays rather than the whole display. Also, we often want to scroll an entire line off the screen rather than just by one position, as the functions in the Liquid Crystal Library offer. This Instructable provides functions to do just that, and so should be thought of as an addition to the scrollDisplayLeft() and scrollDisplayRight() functions in the Liquid Crystal Library.

How to Scroll a single LCD line – Arduino – [Link]

Fuel-gauge ICs help prevent battery clones


Maxim’s family of ModelGauge m5 standalone fuel gauges provides SHA-256 authentication with a 160-bit secret key to make it harder to clone battery packs. The ICs also implement the ModelGauge m5 algorithm, which converts raw measurements of battery voltage, current, and temperature into accurate state-of-charge (SOC%), absolute capacity (mAhr), time-to-empty, and time-to-full readings. by Susan Nordyk @

ModelGauge m5 automatically compensates for cell aging, temperature, and discharge rate. As the battery approaches near empty, ModelGauge m5 invokes an error-correction mechanism that eliminates any error.

The MAX17201 and MAX17211 monitor a single-cell pack, while the MAX17205 and MAX17215 monitor and balance a 2S or 3S pack or monitor a multiple-series cell pack. In addition to high accuracy and age forecasting, the fuel gauges offer low power consumption. The MAX17201 and MAX17211 have a quiescent current of 18 µA when active and 9 µA in hibernate mode. The same specifications for the MAX17205 and MAX17215 are 25 µA and 12 µA, respectively.

Fuel-gauge ICs help prevent battery clones – [Link]

Ambient light and proximity sensors sense distances up to 10cm


With its APM-16D17-05-DF8-TR8 and APM-16D17-06-DF8-TR8 ambient light and proximity sensors, Everlight aims to save energy and reduce unwanted signals and noises when used in smartphones, tablet PCs, residential smart lighting and digital signage applications. [via]

Both series use a specially coated photo diode with an optical response similar to human eyes. They have a common I²C interface allowing them to be driven with a supply voltage of only 1.7V. They are optimized to sense the ambient brightness and adjust the backlight of a screen to the most clear and comfortable settings. For example, the screen gets brighter in shining daylight but darkens in a dark environment.

Ambient light and proximity sensors sense distances up to 10cm – [Link]

EmbeddedLab introduces us TI’s Tiva C MCUs


Shawon Shahryiar @ introduces us to Tiva C series microcontrollers from TI.

The Tiva C series MCUs are high performance ARM Cortex M4F micros. Now what does that mean? Generally speaking the ARM Cortex M series is meant to be used in place of (or simply replace) regular microcontrollers like PICs and AVRs while the A series and R series are designed for application-specific and real-time purposes respectively. The “4” in the “M4F” means it has all of the features of ARM Cortex-M3 along with additional features like Digital Signal Processing (DSP) extensions. Likewise the “F” indicates the presence of a Floating Point Unit (FPU). Thus Tiva C micros are high-end ARM microcontrollers with DSP and FPU support.

EmbeddedLab introduces us TI’s Tiva C MCUs – [Link]

Inside the tiny RFID chip that runs San Francisco’s race


Ken Shirriff teardowns an RFID chip used to track the time each runner took to run the race.

At the beginning and end of the race, the runners cross special mats that contain antennas and broadcast ultra high frequency radio signals. The runner’s RFID chip detects this signal and sends back the athlete’s ID number, which is programmed into the chip. By tracking these ID numbers, the system determines the time each runner took to run the race. The cool thing about these RFID chips is they are powered by the received radio signal; they don’t need a battery.

Inside the tiny RFID chip that runs San Francisco’s race – [Link]

World’s First 1,000-Processor Chip

kilocore_chipby Andy Fell:

A microchip containing 1,000 independent programmable processors has been designed by a team at the University of California, Davis, Department of Electrical and Computer Engineering. The energy-efficient “KiloCore” chip has a maximum computation rate of 1.78 trillion instructions per second and contains 621 million transistors. The KiloCore was presented at the 2016 Symposium on VLSI Technology and Circuits in Honolulu on June 16.

World’s First 1,000-Processor Chip – [Link]