Taking a look under the bonnet of a computer

It takes all kinds at TechShop. On any given day you might see a muscly, tattooed biker contemplatively working away on a sewing machine. Across the room, a little old lady is welding parts for her motorbike. So there’s no reason why I can’t build a computer here. Technology is blind, which is great because I’m blind to how most technology works.

In the case of computers, it’s fair to assume that the vast majority of the 3 billion people who use one every day, have no idea what’s going on under the bonnet either.

So it should come as no surprise that a technology journalist doesn’t know what he’s doing.

Assembling an Arduino is the first in a series of classes offered by TechShop Austin that shows you how to build, programme and use Arduino hardware and software. This is the most popular open source microcontroller board available and was originally designed by a group of Italian artists/designers in 2005.

Through various sensors, or other devices connected to its inputs, it can respond to the surrounding environment in numerous ways.

That is of course, when it’s finished. Right now all I have in front of me is a soldering iron, a printed circuit board, a microprocessor, power jacks, resonators, capacitors, diodes, resistors, Aaaaaah!

Like every adult class I’ve taken, all the other students look like they’ve been building Arduinos for years and just came here today to make me feel uncomfortable.

Before going anywhere near the soldering iron though, our instructor Russell Stanphill, (a former VP at Motorola) gives us a little Physics 101 class on how electricity works (which eases my mind as many other faces suddenly look as if they're about to learn something new).

“The fundamentals of electricity can be hard to grasp because we can’t see it,” he says. “You can feel the effects. But you can’t see it. That’s why a water analogy works well.

“As water is raised into a tower, it is provided with potential energy.

“Due to gravity, it wants to return back to ground. The water pressure exerted on the column of water is analogous to the electrical force. Electricity applies pressure and tries to move its charge down a conductor.

“The diameter of a water pipe is equivalent to the resistance of electricity. When there’s very little resistance, like in a large pipe, a lot of electricity can flow, and vice versa.

“The diameter of the pipe relates to resistance. Resistance is used to control the flow of current.

“Finally current is the amount of gallons of water per minute you could collect in a bucket at the end of a pipe (or the amount of charge you could collect at the end of a wire).”

These three fundamental principles are related by Ohm’s law, which states that the current that will flow is equal to the voltage divided by the resistance.

End of Physics 101

The long and short of it is that all these little bits and pieces need to be soldered onto the circuit board in order to allow an electrical current to flow smoothly so that all the different parts can do their thing. Each part has an essential function required by any computer – from the simplest to the most sophisticated. The board itself not only holds the components but has etched copper traces that connect them together electrically.

The microprocessor is the brain of the board that runs all programmes. The resonator is a quartz oscillator that provides a clock for the microprocessor. The voltage regulator does exactly what it should by taking unregulated power from the power jack to make a consistent five volts. It goes on and on.

Soldering on

Quality soldering is essential to the long-term performance of your Arduino.

The perfect shape for your solder joint should be like a volcano. "Does this have anything to do with Arduinos coming from Italy, " I ask? A stupid question, of course. But the microcontroller's origins are etched into it in different ways.

Not that one thought there could ever be much demand for black-market open-source microcontroller boards, the only way to know your Arduino is authentic is by the location of a small map of Italy on the back.

In reality the process of putting all the pieces together is pretty straightforward. Soldering takes a steady hand but comes pretty naturally after a short time doing it.

Thankfully, the instructor, Stanphill, is both patient and enthusiastic (the two most important strengths in a good teacher). While working with Motorola, Stanphill became close friends with Steve Jobs. Now retired, he has been helping TechShop as a consultant for the last two years. "I was so excited about the maker movement that I voluntarily came out of retirement," he says.

You can tell he loves what he does. Even after a three-hour class he tries to keep us back to look at books and websites that might be of use.

I had one goal for my little microprocessor: for its red light to blink when connected to a power supply. It did. Success. For those who decide to pursue their computer love beyond a first date, there are literally dozens of websites with programmes, software and instructions on how to use your Arduino more effectively.

Here is a list of Russell Stanphill's favourites: www.arduino.cc; www.moderndevice.com; www.adafruit.com; www.sparkfun.com; www.makershed.com