Careful! Don’t Let the Smoke out!

[warning]Careful! Don’t let the smoke out![/warning]

Hopefully you’ve never ruined any electronics device due to applying too much power. Some people have (cough, cough .. the voice of experience) and when this happens the device or component goes up in smoke. In popular jargon it is said to have “lost its smoke“.

When working with various components, always check their voltage ratings and make sure the input voltage does not exceed those limits.  Also, even with correct voltages, if certain components are wired wrong (like polarized capacitors)  they can still  be damaged.

So it pays to always double check things before you hit that power on button!


OBD-II Testing with an Arudino

OBD-II  (an abbreviation for  On-Board Diagnostics, Second Generation) is a set of standards for implementing a computer based system to control emissions from vehicles ( and a lot more ! ).  If you are not familiar with OBD-II you can read more about it here.

I just recently acquired an OBD-II UART board and cable


from, so I can diagnose any car problems. One end of the cable connects to the OBD-II connector on your car, the other end connects to the board.  The board can then connect to any serial port via a 6 pin header that needs to be soldered on.

The 6 pin header connects nicely to an FTDI board

FTDI Breakout 5V

that also sells.  The tutorial about this product shows how to attach an arduino and LCD monitor to capture data from your cars’ computer.

The board did not come with any OBD-II diagnostic / analysis software but there are a number of FREE and commercial offerings to choose from.

I like to write my own software and so I came up with this Python script to inquire for and analyze the OBD information. It is too big to post here so just click on the image to download it.


If you’d like to test the Python code but do not have the OBD-II UART, you can substitute any Arduino you might have lying around. I wrote a simple sketch to emulate the OBD-II information coming from a ‘sample’ car. Just attach the arduino to your computer via any USB cable, load the sketch and run the Python script.

I tested it with my Aduino Nano.
Arduino Nano

Here is the sketch:

Atmel versus PIC Microcontrollers

Many years ago (I am old  ;-)) I was asked which microcontrollers are  best, ones from PIC ( or ones from  Atmel (

At the time I was asked, there was a lot of discussion about chip architecture, instruction sets and which chip was best.

I thought at the time and still feel this way, it depends on too many factors to say which is best.

Certainly with the popularity of the Arduino the Atmega series of chips from Atmel got a boost in popularity.

For most of my projects, I find myself using an Atmega 328p mostly because I can buy it locally in my favorite electronics store cheaply and It is easily programmed with the Arduino IDE.



Fritzing Circuit Design Software

If you need a way to design a circuit or show a nice graphic of it for someone else to follow, you might consider Fritzing from

A quote from their website:

Fritzing is an open-source hardware initiative that makes electronics accessible as a creative material for anyone. offers a software tool, a community website and services in the spirit of Processing and Arduino, fostering a creative ecosystem that allows users to document their prototypes, share them with others, teach electronics in a classroom,and layout and manufacture professional pcbs.


Fritzing software is vector based so you can, drag and drop circuit components, easily re-size and attach wires.

It allows you to make COOL looking graphics like this:


The Fritzing software comes with an extensive libary of components, however there are others who have created libraries of parts too. One of my favorite  Internet  hangouts is They have created a Fritzing library of parts which you can find on Github here.

MicroController Electronics

We live in an exciting age!  Just think about how computer technology has progressed in just one ‘people’ generation!

Electronic devices with smaller and smaller components are infiltrating our lives more and more making things easier.  The ‘Internet of Things‘ is taking over!

My main interest (and I hope yours too) is in electronics and especially how electronics are integrated with microcontrollers.

That is what is all about!

I hope you enjoy the content posted here!

Note: I have separated the posts into two pages. The main post(s) page (which you are viewing) has unique content, i.e., articles I have written. There is another post(s) page (Ecommerce) which contains information, reviews, current prices and links to purchase the various electronics parts which I use and mention in the main post(s) page.  The Ecommerce page is my advertising page and I keep it separate so as not to annoy you. However, please feel free to browse this page if you are interested in purchasing something I mention. If you do purchase something through those links it will help with the costs to maintain this site.

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