Saturday, October 26, 2013

Arduino Bluetooth to Bluetooth Communication

Our Bluetooth project will have two Arduino's talking to each other. This will allow us to have a weather station remote talk to the indoor display system. These modules only accept a 3.3v RX signal, so I added a voltage divider to prevent the Arduino 5v signaling from damaging the module. I have the two modules connected to their repective Arduino's, and set the baud rate and pairing codes using a AT Command sketch. Not successful transmitting data bluetooth to bluetooth yet, but am able to pair from my laptop and my Android phone.

Update! With the help of Mike McRoberts, we found the problem. We have 2 identical HC-06's which are hard coded master or slave from the factory. What we need are the HC-05's, which are field settable for master or slave.

Code available!

Friday, October 25, 2013

Arduino to MySQL Direct Part 2

Chuck has come out with an update to his MySQL connector -

There is a new release of the Connector/Arduino on Launchpad! See The new version supports a number of refinements and a few new features. These include:

  • Improved support for processing result sets
  • Conditional compilation to omit result set handling features to save program space
  • Support for the Arduino WiFi shield
  • New version() method to check version of the connector
  • Simplified download (no more patching SHA1!)

So What is It?

If you have never heard of Connector/Arduino, it is simply a library designed to allow the Arduino platform to connect to and issue queries to a MySQL Database server.

Simply add an Ethernet shield to your Arduino and use the library to connect your Arduino to a MySQL database server. Yes, no more web-based hand waving or third party systems! Cool.

Tuesday, October 22, 2013

Arduino OBD-II Vehicle Diagnostics

A buddy of mine wants insight into how his vehicle is performing as he drives. He sent me a ArduinoDev ODB-II interface (model B) and said "figure it out". So here we go! We will be exploring the onboard features in future posts, and hopefully some of the options available for this interface.

Let's start with what's included:

  • Directly pluggable into vehicle’s OBD-II port
  • Serial data interface (UART or I2C)
  • Regulated DC 5V output (300mA for model A, 1A for model B, powers the Arduino)
  • Accessing all OBD-II PIDs available in the vehicle ECU
  • Embedded MPU6050 accelerometer, gyro, and temperature (model B only).
  • SD Datalogger Shield 
Optional ports for a GPS and OLED Display. There is a bluetooth version as well, but this model doesn't have that.

Monday, October 21, 2013

The Arduino VGA Interface

Many of our projects need more in the area of displaying data, so we are putting together a VGA interface. Now the Arduino is pretty under powered when it comes to producing a video signal. so we are using our smart interface concept, and dedicating a DIY Barebones Arduino to producing the video signal, offloading that function from the host micro controller. It's very low resolution, and only 16 color, but will work with any VGA monitor or vga enabled TV. Follow along as this project progresses. For a high resolution, high color version, see

If you would like to participate in the development process, I will send you a prototype version for $30, and replace it with the commercial board when it's produced. Email me at