My new raspberry pi 2 model b arrived!

I really should write up what I did with my other raspberry pi in my other post, like I promised...

Basically, I interfaced it to my security intercom in my apartment via a relay so I could unlock the security door with my iphone, because I lost my security key and my strata wanted to charge me $150 for a replacement.

It has since been decomissioned as I have moved house(which meant I had to buy a new key from the strata anyway... but since the strata management had changed it was only $75), but I will write it up when I get around to it (could be a while as I have noticed that I haven't posted on this blog for a looong time!)

It is currently being repurposed as a time machine for backing up my macs. Not sure what I will do with this baby - its got 1gb of ram and a quad corm arm processor. It would be nice to hook up to my stereo to stream music via airplay or squeezebox... it probably overkill for that purpose!

raspberry pi prototyping kit from adafruit arrived today

I already have a project in mind - an internet connected security door buzzer so I can open the front door to my apartment block with my iphone. Stay tuned for construction details

Subaru Outback O2 sensor replacement...

In a previous post I mentioned how I had managed to diagnose a check engine light on my 2005 Subaru Outback and tracked down the fault to a burned out heater coil in the front o2 air/fuel or lambda sensor.

After baulking at paying $530 for the official Subaru part I tracked down a compatible Denso sensor part number 234-9015 on ebay for only $110 shipped from the USA. Then it lay around on my shelf for a month or two, as I actually had no idea where this part was supposed to go.

I didn't have a service manual, so I watched a few you tube videos, and read some forum posts, then finally got under the car and had a look. Finally I saw what looked like an O2 sensor, it was on the exhaust system as expected, but there was barely any room under the car, and it looked like I needed a special tool- a 22mm O2 sensor wrench to remove it anyway. I duly ordered the tool from ebay for $17, then one Sunday afternoon parked the car with the drivers side wheels up on the kerb so I could squeeze under the car and replace it.

I came off easier than I expected, but it looked a little different to my replacement part. Never mind, I plugged it in, also noticing that although the plug fit, the connector was not quite the same either, and would need to be taped to hold it together.

It wasn't till I started the car and checked the OBD codes on my Mac with the excellent Movi software that I realized the damn error codes were still present... only then did it twig that I had mistakenly replaced the rear O2 sensor!!! Finally, I located the front O2 sensor, but it was up near the drivers side wheel obstructed by the plastic engine undercover, and looked like it would be a real pain to replace from  under the car, as it would involve removing the engine undercover. After much cursing, I swapped back the original O2 sensor, incredibly glad that I didn't remove it by cutting the wires, and resolved to pay my mechanic to fit the replacement sensor a my next service.

But it actually turned out easier than I expected - I opened the bonnet and removed the air intake duct that goes into the air filter so I could get a better look and observed that it was quite possible to remove the O2 sensor without having to muck about under the car. It was about as hard as replacing a light bulb, then all I had to do was clear the codes and BAM! No more annoying engine light and flashing cruise control indicator distracting me on the dashboard.

So all up it cost me $110 for the part, $17 for the tool, $20 for an OBD code reader and $50 for the software... all up $197 instead of $530 for the official part, plus labor.

So awesome, I blogged about it...

iPad 2 glass digitizer replacement...

My iPad2 had an unfortunate encounter with the pavement recently resulting in a broken glass digitizer.

Replacements are readily obtainable off ebay for around $50 so I thought I would have a crack at fixing it, which is not as easy as you would hope. That's because Apple have made their best efforts in the name of built-in obsolesence and glued the screen on. This means that in a few years when your perfectly functional iPad's battery starts to fade, you'll probably have to throw it away and buy a new one because removing the screen to access the battery is a major ordeal.

I was lucky in that I did not have to worry about keeping the screen intact, since I had a brand new replacement.

I used the iFixit teardown guide, as well as some hands on support from my friend Spoonie, who had already done his own teardown -without him I'm sure it would have taken much longer.

Anyway, I discovered a few things on the way...

iFixit recommends you use a heat gun to loosen the adhesive, which helps a great deal. However, make sure it is not too hot, as the screen sits on a thermoplastic bezel, which melts and deforms if it gets too hot. I discovered this the hard way, and as a result the new screen doesn't sit flush like it should. I managed to crack my brand new screen trying to reseat it with a little too much force.

So, I have bought another screen, a replacement bezel and some proper adhesive to glue the new screen on.

Hopefully the job will be much easier the next time around!

Installing an SSD without reinstalling windows

Introduction

Congratulations on receiving your new SSD disk! The best way to make use of it is to use it as your system disk and local subversion cache for lightening fast boots and builds.

It is possible to do without reinstalling windows and all your software using windows inbuilt tools such as Windows Backup and Disk Manager. This guide applies to Win2k8r2 but it might work for other OS versions

Step 1 - Install your SSD

You may need to tweak the BIOS to enable the SATA port if windows can't see the disk. Also make sure the SSD is higher in the boot priority than your existing system disk

Step 2 - Shrink your OS disk

Windows backup will only restore to a disk that is at least the same size the original volume. Delete any unnecessary files and shrink the volume using Disk Management. If you are lucky it will be small enough to restore to your new SSD. If you are unlucky there will be some unmovable files such as page files, or indexing files that prevent the disk being shrunk.

To remove the page file, disable virtual memory and reboot the computer

I found I had to disable indexing as well. Select "Indexing Options" in the control panel, remove all the folders or disks under "Included Locations". Then rebuild the index using the "Advanced" button.

Now try shrinking again. If its still to big you are out of luck, you will need to reinstall windows and all your favourite software.

Step 3 - Backup your OS Disk

Use Windows Backup or Windows Server Backup. Select Backup once and choose a custom backup - you want to select "Bare metal recovery", "System State" and your system disk (C: drive). I also has an additional partition called "System Reserved" that I backed up as well just in case. Choose a destination for the backup, either an external disk or your other internal disk and wait for the backup to complete.

Step 4 - Restore your backup

To restore a bootable system you will need to reboot with the OS install disk. I also disconnected the original windows disk just in case.

Choose restore your backup. Now at this point it failed with a cryptic message about a data disk having an active partition. This apparently was because my SSD had some stuff on it. I went to the commandline and ran diskpart clean - which deleted everything from the SSD. After that the restore proceeded successfully.

Step 6 - Reboot and enlarge your system disk

You system should reboot successfully and super quick thanks to the new SSD, but because you shrunk the windows partition in step 2 there may be some unallocated space on the disk. Use diskmanager to enlarge your c: partition and reclaim this unused space.

Step 7 - Enjoy your fast booting computer and lightning quick build times

I hope this guide was useful.

WARNING

I initially had a problem when I reconnected my original HDD with the OS on it. My dell optiplex 755 didn't remember that i changed the boot order, booted off the old disk and screwed the startup for the SSD. I suggest reformatting your original HDD to remove all trace of the OS before restarting with it connected to your computer.

Alternatively you may prefer to use the free disk migration utility from Intel

http://downloadcenter.intel.com/detail_desc.aspx?agr=Y&DwnldID=19324

However, this will not work with server grade OSes like Win2k8