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Light Bar “Relative Comfort” Thermometer with NodeMCU

Light Bar “Relative Comfort” Thermometer with NodeMCU

Create a wireless "relative comfort" light bar thermometer by broadcasting temperature data across multiple ESP8266 modules running NodeMCU using MQTT.


Projects Sep 28, 2015 by Patrick Lloyd
How to Add Bluetooth to a Ceiling Fan

How to Add Bluetooth to a Ceiling Fan

How to add BLE capabilities to a wireless ceiling fan by incorporating the nRF51 in the remote control. Part of our series on the nRF51.


Introduction to FreeRTOS on the nRF51

Introduction to FreeRTOS on the nRF51

This article demonstrates porting FreeRTOS to the nRF51 with a softdevice so you can use an RTOS with the BLE functionality.


The New Wireless Thread Network Protocol

The New Wireless Thread Network Protocol

Thread, a network protocol released July 2015, is optimized for the connected home network. It is IPv6 based, uses IEEE Standard 802.15.4 and runs on existing hardware.


BLE using nRF51: Creating a BLE Peripheral

BLE using nRF51: Creating a BLE Peripheral

How to create a custom BLE GATT peripheral using the nRF51 by creating a service and characteristics.


How to Communicate with a Custom BLE using an Android App

How to Communicate with a Custom BLE using an Android App

Learn how to communicate with a custom BLE peripheral using an Android device.


EFM8 Sound Synthesizer: Playing Melodies via USB

EFM8 Sound Synthesizer: Playing Melodies via USB

Part 3 in the “How to Make an EFM8-Based Sound Synthesizer” series.


Projects Sep 17, 2015 by Robert Keim
Introduction to the MQTT Protocol on NodeMCU

Introduction to the MQTT Protocol on NodeMCU

MQ Telemetry Transport (MQTT) is a popular low-overhead messaging protocol used by many IoT devices to communicate. This tutorial will show the user how to to set up a basic MQTT network using Python on his or her computer and an ESP8266 running the NodeMCU firmware.


Projects Sep 15, 2015 by Patrick Lloyd
BLE using nRF51: ARM-GCC Build Environment

BLE using nRF51: ARM-GCC Build Environment

How to set up the build environment for the nRF51 system-on-chip using makefiles and ARM-GCC.


EFM8 Sound Synthesizer: Driving the Speaker

EFM8 Sound Synthesizer: Driving the Speaker

Part 2 in the “How to Make an EFM8-Based Sound Synthesizer” series.


Projects Sep 11, 2015 by Robert Keim
ZigBee vs Bluetooth and Bluetooth Smart

ZigBee vs Bluetooth and Bluetooth Smart

ZigBee, Bluetooth and the newer Bluetooth Low Energy (BLE/Smart) are all communication protocols for Wireless Personal Area Networks (WPANs), but they are optimized for different applications.


EFM8 Sound Synthesizer: From Square Wave to Sine Wave

EFM8 Sound Synthesizer: From Square Wave to Sine Wave

Part 1 in the “How to Make an EFM8-Based Sound Synthesizer” series, which will design a sound synthesizer that can play standard musical notes. We will accomplish this using a low-cost, small-form-factor EFM8 microcontroller in conjunction with a few external components and a speaker.


Projects Sep 04, 2015 by Robert Keim
An Introduction to the Wunderbar

An Introduction to the Wunderbar

Learn how to set up the Wunderbar platform to begin building your own IoT apps. This will demonstrate the "Can't Touch This" and "Tell Me When" demo applications to measure WunderBar sensors and perform actions based on them. Some of the major bugs are discussed.


Projects Aug 29, 2015 by Patrick Lloyd
FSK Explained with Python

FSK Explained with Python

This article will go into a bit of the background of FSK and demonstrate writing a simulator in Python.


Make an Automatic Water Softener Reporter

Make an Automatic Water Softener Reporter

Create a smart home by displaying the current salt level of your water softener with the CC3200 and a proximity sensor.


How to Use MAX232 to Communicate Between a PIC and a PC

How to Use MAX232 to Communicate Between a PIC and a PC

This is one simple way to control a LED, fan, relay or solenoid with a computer and a PIC.


Build an Audio Detector

Build an Audio Detector

Detect audio with an electret microphone and a TI CC3200 Wifi microcontroller. This handy project will allow you to set up an audio detection device that can be used to catch your roommate stealing things from the fridge or send you an alert if the noise in your room goes above a certain threshold.


An Intro to Multiplexing: Basis of Telecommunications

An Intro to Multiplexing: Basis of Telecommunications

Multiplexing was developed in the early 1870s, but it’s become much more applicable to digital telecommunications in the late 20th century. Today, frequency division multiplexing (FDM), time division multiplexing (TDM), and wavelength division multiplexing (WDM) have become an extremely important asset to telecommunication processes and has greatly improved the way that we transmit and receive independent signals over AM and FM radio, telephone lines, and optical fibers.


Transformer Isolation

Transformer Isolation

An in-depth look at transformer isolation. Electrical isolation is necessary to protect circuits, equipment, and people from shocks and short circuits, as well as to make accurate measurements. Isolation transformers are one way to go.


Mathematical Construction and Properties of the Smith Chart

Mathematical Construction and Properties of the Smith Chart

Smith Charts are an extremely useful tool for engineers and designers concerned with RF circuits. This article covers the mathematics behind creating the chart and its physical interpretation.