I2C Multiplexer Shield Testing
I built an I2C multiplexer shield using an Arduino prototyping shield from SchmartBoard a couple of weeks ago. The shield uses a PCA9548A I2C multiplexer and switch chip from Texas Instruments.
Category: AVR/Arduino
Reverse Engineering the Syma S107G IR Protocol
I got a Syma S107G IR controlled helicopter for my son a while ago. This tiny remote control helicopter is a rather amazing toy. Not only its movement is very stable, but the rotor speed, forward backward movements and turning…
Code For MCP4821/MCP4822
Microchip‘s MCP4821/MCP4822 is a low budget 12-bit digital-to-analog converter. MCP4821 is the single channel version whereas MCP4822 has two channels that can be latched simultaneously. Both chips have internal band gap references and can be controlled via SPI.
Digital Metronome — Revisited
Last year, I wrote about a simple digital metronome project. While the device worked pretty well there are a few changes that are to be desired.
Simple Zener Diode Tester
In this post I will show you a simple Zenner diode tester circuit, when coupled with a PWM generator it can be used to measure the breakdown voltage of Zener diodes. Or more generically, it can be used to measure…
Arduino Library For MCP342X
Last time, I discussed how to interface TI’s ADS1112 16-bit delta-sigma A/D converter with Arduino. Today I am going to introduce you to a set of easy-to-program A/D chips from Microchip. MCP3246/7/8 are a family of 16-bit Delta-Sigma A/D converters…
Interfacing ADS1112 With Arduino
ADS1112 is a 16-bit delta-sigma A/D converter. This A/D chip has an I2C interface, a 2.048V internal voltage reference and performs a self-calibration on each conversion. These characteristics make it very easy to work with an MCU such as ATmega328p.
5A Lab Power Supply With Digital Readout
I got a used 250VA power transformer that was removed from equipment a couple of weeks ago. The transformer has a dual 10V AC output and a few auxiliary voltage outputs. The 10V winding is rated at 10A, I thought…
AD7705/AD7706 Library Revisited
About a year ago, I wrote a simple library for interfacing AD7705/AD7706 with Arduino. The library works, but it requires some decent knowledge of the underlying chip, which had made it somewhat difficult to use. Most issues users reported can…
Interfacing LTC6904 With Arduino
LTC6904 is a programmable oscillator which is capable of generating frequencies from 1kHz to 68MHz. The oscillation frequency can be changed via the I2C interface and thus makes it very easy to interfacing with MCUs.
A Self-Balancing Robot – III
In part one, I went over the theory behind the self-balancing robot and in part two, I showed you my build using a modified toy truck. In this post, I will walk you through the code and show you the…
A Self-Balancing Robot – II
In my previous post, I explained the theory behind the self-balancing robot at a high level. Here, I will discuss the actual build in more details.
A Self-Balancing Robot – I
Building a self-balancing robot is one of those things that every hobbyist and engineer want to do. But there are a few hurdles for a lot of people. There is the theory on the one hand and then there is…
So Why I like Arduino
You probably know this already from just reading some of the posts in my blog. Like millions of others, I am a big Arduino fan. So I thought I would share my side of the story and you can decide…
ATmega328 Fuse Bit Setting for 3.3V Vcc
By default, ATmega328 used in Arduino (such as Uno or Duemilanove) operates under 5.0V. Sometimes though it is necessary to use 3.3V supply voltage to accommodate peripheral circuits that cannot tolerate 5.0V.