Something I said ten years ago comes back to not haunt me: in fact, I was quite pedestrian about the whole thing.

My friend Rich was house-cleaning and came across an interview that I did with the Irish media about ten years ago, while we were running our company, Aurium. One thing really jumped out at him was the answer I gave to one particular question:

Q: What will we be using to access the Internet 10 years from now?

A: I don't think we'll even think about it in those terms. It's a bit like asking what sort of device you use to access the telephone network. In 10 years the internet will be so ubiquitous that we won't even think about it.

I remember giving this interview, and it feels weird in a number of ways. Firstly, when you see an "expert" being interviewed in a newspaper, don't assume that he's there because of his expertise. He could simply be a randomer with a good PR firm, which is what I was: the article was "placed" as part of our public relations campaign. Secondly, I was right in terms of where the technology was going, but that wasn't due to any vision on my part: it was simply a function of being part of the development of that technology and seeing from the inside where it could go. There are plenty of alternative futures where things happened differently and the internet didn't take off as it did. Had we had a major security crisis or breach of privacy in the first few years, that might have killed people's confidence enough to damp-down the uptake.

What really struck me, though, was exactly how pervasive the technology did become. As it happens I'm in London on business with my colleague Graeme, and it's instructive to look at all the things we did on the internet -- and indeed from mobile gadgets. Firstly, I checked-in on the British Airways cellphone app and so didn't need a printed boarding pass. (This is an application we first suggested ten years ago, incidentally: a boarding pass is just a token, so why not text someone a long number to identify themselves with?) Then we arrived not knowing where the hotel was, but a combination of the Tube Map app and Google Maps soon directed us via train and foot, from Gatwick airport to Pimlico. We looked up places to drink and a place for dinner the next day using TripAdvisor, again navigating there with Google Maps, and made recommendations for the various places for other travellers. (Oh, and incidentally checked in for the return flight while sat in the pub -- very civilised, I must say.) We found a coffee shop while we were waiting for our meeting, which itself took place in a venue whose location we also didn't know relative to our hotel. I collected the different bookings and details in TripIt, which shared them into my Google Calendar so I didn't have to take note of them. And I took some pictures and shared them on Facebook.

But actually the most surprising thing isn't the technology, or the mobile device, or the fact that it all actually works together in practice: it's that real people actually do it, and I don't think I'm unique in using all this mobile internet technology when travelling. We pretty much take for granted the idea of finding our way in a new place without preparation: neither Graeme nor I ever even thought about how we'd find the hotel or the meeting venue beforehand, we just got up and did it.

Looking back, I'm not surprised we (the technology community) got the technology to work; I'm not even really surprised at the availability of mobile internet and a load of apps to make use of it; but I must confess to being slightly surprised that at the acceptance of all the gadgetry amongst the general population, enough to generate an ecosystem of companies who work together and create more value from their interoperability. It's something we always said would happen, but it's quite strange to see it in operation, and it's a positive achievement we shouldn't forget about.

It turns out there there are quite a few versions of the "same" components out there. Uploading sketches to an Arduino-on-a-breadboard is trickier than it first appears.

The Arduino-on-a-breadboard showed that we can get a lower power version of the same architecture. However, in doing the measurements I used a microcontroller already loaded with the code I used for the power measurements (sleeping and blinking). Trying to change this code and upload it via the USB breakout board didn't work -- repeatedly.

It turns out that the breadboard tutorial on the Arduino web site is actually flawed for the current versions of the components concerned. There are actually two problems: the microcontroller needs to be manually reset before uploading a sketch; and the USB breakout board needs slightly more supporting electronics to talk to the microcontroller.

The first problem stems from the microcontroller needing to be reset before code can be uploaded to it. Essentially the reset makes the bootloader wait for code for a few seconds, and start the existing program if none arrives. On older Arduino models you have to physically reset the board using the reset switch just before uploading a sketch; on newer models, this reset happens automatically. Setting up the breakout board to reset the microcontroller immediately before it tries to talk to it will solve this.

The second problem is more subtle. The USB breakout board is actually a USB to serial converter. The tutorial suggests that it is enough to connect the transmit and receive (Tx and Rx) lines to the microcontroller, but this turns out not to be the case: one also needs to connect some handshaking lines to make the system synchronise and communicate correctly. I eventually found a post that explains this: however, that post is flawed too, because it relies on a particular pin-out for the USB breakout board that's different tothe one I have. So here's a debugged explanation of what needs to happen.

We need to connect the basic TxD, RxD, Vcc and Gnd lines on the breakout board as you'd expect. The picture to the right shows the the underside of my breakout board, with the pins named. If we number the pins counter-clockwise from the top left (so DCD is pin 1, TXD is 9, TXLED is 11, and VCC is 13), we connect pins 3 and 10 to ground, pin 13 to power, pin 9 to pin 2 of the ATMega microcontroller, and pin 5 to ATMega pin 3.

What now also need to happen is that we need to connect the CTS and DTR lines to something. DTR (Data Transfer Ready) is sent low when the USB has data ready: we want this to trigger a reset of at ATMega. We then need to send CTS (Clear To Send) low so that the board starts sending data. This is basic serial-port handshaking. The timing can be accomplished using an RC circuit consisting of a 100ohm resistor and a 100nF capacitor attached appropriately. Putting this circuit onto the breadboard sorts out the handshaking, and the Arduino IDE happily uploads sketches just as it would to a "real" Arduino.

The net result of this is to add some more wiring to the USB end of the Arduino breadboard:

Note the resistor and capacitor. (The red wire crossing the breakout board is a Gnd connection, needed because my breadboard only had single power rails top and bottom.) The circuit involved is as follows:

For my particular breakout board shown above, this means connecting pin 7 to the capacitor and pin 15 to the following resistor. (It's this last step that the post gets wrong -- or at least uses a different pin for CTS.) The net result is an Arduino-on-a-breadboard that looks like this:

Somewhat more complicated, but rather more functional.

I think you have to maintain a sense of perspective about these issues, annoying as they are: in many ways it's good that the components change and evolve rather than staying exactly the same, as it means that they're being developed and refined over time. On the other hand, it means you have to be very circumspect about following blindly the tutorials and explanations on blog posts from even a relatively short time ago.

Putting an Arduino together from scratch lets us look at where the power consumption might be reduced -- and is just an interesting thing to do anyway.

One of the most exciting things about the Arduino is that it's open-source, so you can build them yourself -- and potentially vary the way they're put together for specific projects, which is very useful as a starting point for people (like me!) who aren't hardware engineers.

The main challenge for sensing with Arduinos seems to be their power consumption, and the obvious way to address this is to see whether there are things to be done to reduce the power drain, for example by addressing the issue of the quiescent current of the power regulator.

As a starting point, I used an on-line guide to build an Arduino on a breadboard:

Actually this isn't a "full" Arduino as the analogue to digital converter (ADC) isn't properly set up, but it has the basic components of microcontroller (the same ATmega 328P as on an Arduino Uno), LED, reset switch, power, and USB. The breakout board at the left-hand side is the USB adapter, while the cluster of components on the right is the power regulator. At present I'm powering from batteries; one can also power from the USB, or from a wall power supply via another breakout board, but this way allows the same power measurement regime as earlier.

Measuring power for a simple "blink" program gives the following result:

So in deep sleep mode the system draws about a seventh the power as a "real" Arduino. This is all down to the choice of voltage regulator: an L7805 with a design maximum quiescent current of 6mA. To put this into perspective, a system that could last a week on a standard Arduino board would last the best part of two months in this configuration. Put another way, we can build a sensor mote with an Arduino architecture and dramatically increased lifetime by changing a core component and using SleepySketch to keep the system asleep by default.