Fun with the Raspberry Pi

If you've heard about the Raspberry Pi, (wikipedia, elinux.org) a $35 single-board Linux computer, you probably won't learn much new here. The main point of this post is that I got mine to boot, so I do have one or two small bits of advice to pass on to those working toward that goal. First, photographic evidence (veracity: if I were faking it I wouldn't put a big reflected flash in the middle of the screen).

Here's the board booting. Booting (and everything else) is a little slower on the Raspberry Pi than you're probably accustomed to. But then, hey, it's $35, and you can stuff it into whatever piece of hardware you're building and have full-blown Linux with X Windows. So live with it.

My experience has been that at least in the near future, it's not really $35. Here's what happens: the Raspberry Pi folks build a bunch of boards and sell them for $35, but they get picked up by people who want to resell them, so you end up getting yours on eBay for somewhere in the $55 to $70 range. Eventually this mischief will end and the price will stabilize.

 Photographic evidence number two: the board has booted into X Windows. This is using the recommended-for-beginners Debian-based distribution, 2012-09-18-wheezy-raspbian.zip, which unpacks into 2012-09-18-wheezy-raspbian.img, and obviously the date in that name will be updated periodically.

So here are the tips for fellow beginners:

• First, remember this board is designed for complete novices, and even, heaven help us, artists. Do not despair, you ARE smart enough to get it working.
• The Raspberry Pi folks warn you away from micro-SD cards, but the one I'm using works fine.
• You may find that your keyboard is mapped in a funny way. My (@) key and (") key were swapped, and the (#) key was mapped to a British pound sign (£). One solution to this appears here. Mine was to create the file /home/pi/.xsessionrc which contained this line:

setkbmap us -option grp:ctrl_shift_toggle

A better approach to the keyboard issue is one of the options in raspi-config (the first thing that appears on your screen after all those boot messages finish). Look for "keyboard configuration" and select the canonical U.S. keyboard choices.

Everything else seems to be working, but I haven't tried to do much yet. I have no idea how to talk to GPIOs or other peripherals yet, but I've done that with other Linux boards and expect that my past experience will get me there pretty painlessly. That, and there is a HUGE community for this thing.

Looking forward to checking out Adafruit's WebIDE when time permits. The development system runs as a web server on the board, and you develop in the browser on your laptop over a network connection.

And now for your viewing pleasure, assorted Raspberry Pi pr0n:

 

 

Adrian Bowyer interview, Computerworld

Here is the start of the four-page interview. Much of this is stuff that's been published before. Two parts I found interesting appeared on the third page.

Are there plans to modify the current design to replace non-reproducible parts such as bolts with parts that can be manufactured on the machine itself, bringing the overall RepRap design closer to 100 per cent self-reproduction?

Yes - that is definitely one of the evolutionary paths to greater reproductive success. For the immediate future I will be concentrating on widening the list of materials that RepRap can build with (starting with electrical conductors). That widening will implicitly raise the proportion of parts that it can make for itself, of course.

The Fab@Home people have already done a few embedded circuits by printing with conductive silicone. Making circuitry will be a very important ability for these machines.

Can the RepRap recycle what it manufactures?

Yes, recycling has been built in from the start... The main plastic we are using is polylactic acid...

But I want to move to using a non-biodegradable resin. This too is sourced from biomass, but is stable in the ground. That means that the more reprapped goods that get made from it and thrown in landfill, the more carbon is taken out of the atmosphere and locked away for good. And, in 200 years when we have taken so much carbon out of the air to make stuff that anthropogenic global cooling is starting to be a problem, the landfill sites become our strip coal mines to save us.

This is the first time I've ever heard anybody advocate for putting stuff INTO landfills as an environmental measure. An interesting approach to carbon sequestration.