Tuesday, 24 July 2012

Hello, good evening, welcome to nothing much

Welcome, gentle reader, to my blog of adventures in geekery.

Since I heard about the Raspberry Pi project I've been getting progressively more and more excited about it. I'm of the same generation as the RPi's creators, the generation of bedroom programmers and electronics hobbyists who grew up to become the engineers of today, so I can appreciate what they're trying to do with it as a way to introduce kids to programming. But it's also a great platform for more experienced tinkerers to play with, as it can easily be powered by batteries and at under £30 you don't have to be too worried about breaking it. The early adopters have had their RPis for a while now and come up with some great projects like this one

Due to the somewhat distracting arrival of our second child I've not pounced on the RPi as quickly as some, and by the time I'd registered my interest there was a waiting list before they'd even take a pre-order. But the orders opened up earlier this month and I placed mine last week, apparently it's now been dispatched so I'm getting giddy with excitement. Unfortunately the RPi doesn't currently come with all of the bits and pieces you need to get started, you need to order those separately and I'm going to have to wait for those. There's not much I can do without a power cable and the one I ordered isn't due for a month (!), so I'll have to see if I can use my iPad's mains to USB adaptor until the dedicated one turns up though I've seen some reports that it's been found to be inadequate. I've not ordered a powered USB hub as the decent ones are more expensive than the RPi itself, though having read a bit about power requirements and polyfuses I'm not so sure I can get away without it. Hub or hubris?

And that brings me clumsily to the point of this blog - essentially a lab book with style sheets, to keep track of my Raspberry Pi projects and other geeky projects I'm up to. It's purely for my own benefit, though should anyone other than myself and my mum read it then all the better. However as most of my friends are people from college or work colleagues, many of whom are far smarter than me and more knowledgeable about this stuff, I expect they'll only read it for the schadenfreude gleaned from my inability to perform simple tasks such as setting up SSH (must be the firewall, or I'll have to get out Wireshark).

So what have I got planned? Well, I've seen enough hardware bringups to be painfully aware that it's best to walk before I try running - let me just get the bleedin' thing plugged in and booting reliably first. Then I can try a few simple projects, maybe a Squeezebox type thing? After that I've got my eye on those GPIOs, and I'm wondering what I can wire up to them. One of my favourite toys when I were a nipper was BigTrak and I was thinking of making a programmable robot type thing, maybe add a camera, a few sensors, battery pack or really long power cable, etc., then it's all "just" software. There are lots of pre-made robot parts which I could use, the question is how much I want to make myself? Maybe I should just buy a BigTrak, chuck out the microcontroller and use the chassis?

Fifty-Nine Icosahedra screensaver (in windowed mode
for screenshot) - looks better when moving, but still
not good
As for other geek projects - they're currently languishing, damning reminders of the fact that I'm not a completer/finisher. I've been trying to get some C++ practise in an environment where I'm not afraid of breaking stuff (i.e. not work) and I've wanted to do some 3-D projects since I wrote a crude 3-D engine in college. One project is an animation tool which will do inverse kinematics, but after initial success in rendering meshes and skinning them with DirectX (and that was a mission and a half, I tells ya) I decided to switch to OpenGL and got bogged down in the code which loads in resources and follows references to more resources. So that's on permanent hold until I can be bothered with it again. I also wrote a screensaver which renders the Fifty-Nine Icosahedra. The hardest bit was recalling enough GCSE-grade trig to sort out the geometry, but once I got there it gasped into life and... it was a bit disappointing really. Though there are some really weird shapes, on the whole they're a bit samey. It really needs someone with a girlier eye to pick a decent colour scheme, or maybe it'd be better with a single colour, some light sourcing and anti-aliasing, and it could do with some funky transitions between the shapes. Also I tried it at work where it really doesn't agree with my dual monitors, though I'm told that's a problem with many screensavers. I might resume work on that once I get over my disappointment. I wonder if it'd work with the RPi's OpenGL ES? It already works under  Windows or Linux, might need some minor mods to the XWindows code

So that feature-length pilot was a small taste of the hi jinks to come. With luck my Raspberry Pi will arrive soon and the next instalment will be all about how easy it was to set up. Or have close-ups of the voltage regulator with a neat white hole burnt through it.