Monday, July 9, 2012

A piece of homemade raspberry pi

Hurrah!  My (first) Raspberry Pi system-on-a-chip little computer is here.

These things are selling like hot cakes (half a million sold so far, as I understand it).  They have practically been 'unobtainium' due to the demand and the distributors have had to limit orders through a system of registration and invitation.  This isn't the first little 'full featured' ARM-based computer, and there are more new designs and products popping up now to compete, but the Raspberry Pi somehow managed to go 'viral' (as viral as such a geeky thing will ever get) because of three things I think:
  • The people behind it and their stated vision
  • The really small size, but completeness of the hardware spec
  • The really low price
The Raspberry Pi foundation was created to somehow get back to those simpler days of computing when kids could catch the computer bug and experiment with both hardware and software, learning how to program and how to make computers do interesting things like controlling equipment, lights, heaters, making sounds and music, reacting to noises and speech etc.  The Raspberry Pi in fact is supposed to be a similar low-cost, adaptable, platform for experimentation that my generation had in the eighties though the amazing genesis and evolution of 8-bit home computers.   Moreover, the Raspberry Pi hearkens back to a particular British 8-bit microcomputer wonder called the BBC Micro that was specified, designed purposefully for the BBC's computer literacy project in the early eighties and built by a company called Acorn.  This computer was delivered in "Model A" and "Model B" variants, which is exactly what the makers of the Raspberry Pi have also chosen to name their two versions (Model A being slightly simpler and cheaper).

The BBC Micro was truly a breathtaking product in its day.  The geniuses that specified what this computer would be, were so focused on creating a general, highly-adaptable and extensible system that they created a legend.  The only problem with the high-spec of the machine was that it was relatively expensive.  I remember lusting after it, but my allowance (we called it "pocket money") was nowhere near enough to afford the £399 (if I remember right) that was the asking price for a "B".  I had to make do with the £129 Sinclair Spectrum (marketed as a "Timex" over here, and not very effectively by all accounts, given the stiff competition).

The Spectrum was an everyman's machine and probably had the success it did precisely because of my demographic and our lack of disposable income!  While it was a great little machine, the BBC towered over it in sophistication and sheer potential.  These days, I have a BBC Master (the 'version 2' of the BBC Model B) on a desk, not far from where I'm writing this... just for nostalgia really, but also because it's STILL an experimentor's dream.  No other computer I've ever seen has had so many simple hardware interfaces and such great system software to access them.  The Raspberry Pi is indeed an attempt to recreate this in modern times. 

One other little factoid that connects the Raspberry Pi (and that phone you own, and your iPad if you have one, and probably your TV, car and a myriad other devices in your life) is that the Raspberry Pi uses the ARM processor.  Most people know that their PCs use Intel processors.  These chips started out simple enough in the early 70s, but Intel has basically been adding layer after layer of complexity ever since.  While these CPUs give our desktop computers sheer brute force processing power, they consume a vast amount of power to do this and they generate massive amounts of waste heat.  The ARM processor started out with a vision of power with simplicity and has stayed very true to this vision ever since.  Besides being technically able to deliver adequate processing power for less power and heat, which make the chip far more appropriate for small electronic devices, ARM also has a completely different business model: they don't make the chips themselves, but rather they license their designs to companies that make chips.  This combination has created an explosive growth of the technology - it's in practically every device other than desktop computers.  Intel have had major attempts to disrupt this pattern, but so far have not succeeded.

What many people do not know is that ARM started life as a proprietary CPU for a next-generation BBC Micro.  ARM actually stood for "Acorn RISC Machine" (RISC itself being the acronym of "Reduced Instruction Set Computer", the technical approach for limiting the design complexity of a processor).  ARM was a major investment and amazingly visionary for what was still a small household computer manufacturer.  Eventually, Acorn built an amazing new computer around it called the Acorn Archimedes.  Unfortunately, as it so often the case with grand product designs, the computer made it to market too late to dominate, and some highly capable 16-bit machines were appearing from the American market (the Atari ST and Amiga 500).  So, the Archimedes gradually faded into obscurity, along with Acorn the computer maker... but ARM was spun off and did kinda take over the world.  That's also a familiar business story... sometimes the biggest visions win, but not for their original founders.

The BBC Master in my office has gone full circle.  The sheer flexibility of these machines has meant that many have been discovered in the new millennium, still controlling pumping stations or collecting and sending data to other computers.  My computer now sports a completely modern solid state disk, which its 1980's disk operating system handles with aplomb.  However, the other major upgrade inside the case is loaded with gravitas.  The BBC was always designed to support plug-in alternative CPUs.  Back in the day, there were products to add Z80s and even Intel chips as additional processors (the native 6502 process was amazingly designed to retreat into the background as an I/O coprocessor in this eventuality!).  Today, my BBC Master proudly incorporates a modern ARM daughter card.  

Of course, this is supposed to be a blog about a new kind of car.  While it's a bit of a diversion to get into computers, the connection of course is that I intend to host my Raspberry Pi in my Karma.   In a way there's another, albeit more philosophical connection.  The Karma is a BBC Micro kind of product: innovative, slightly ahead of its time, erudite.  It's a risk by some brilliant people on a brand new, flexible, technical platform.  For me, it certainly feels avant garde - exciting to own and be a part of.  Hopefully though the Karma will succeed on its own merits, as its unlikely there's anything like the equivalent of Fisker's "ARM" lurking in the mix.

So, I've assembled all the major components I need to start building out my little in-car data processor.  The internet connectivity is already in place, thanks to the Rogers LTE adapter.  I now have the main pieces to access vehicle data and run software:

The last essential piece will be an 802.11 wifi adapter so the Raspberry Pi can join the OBD Key's ad hoc wifi network to obtain vehicle telemetry (while also connecting to the WAN via LTE).

I have just started playing with the card, by booting it up (the SD card shown has been loaded with one of the available Linux builds specialised for the Raspberry Pi).  Lots of fun to be had in the near future as I learn and experiment more.

No comments:

Post a Comment