Data recovery

Fri, Nov 13, 2009  in Blog using tags Uncategorized

Earlier this year, my home file-and-everything-else server suffered a failure of both case fans which went unnoticed because it’s sitting in a hard to get to part of a cupboard and NetBSD doesn’t (yet) have drivers for the environmental monitoring hardware on the motherboard.

The constantly increased temperature in the case rapidly caused the failure of a head in the hard drive. Unfortunately, I only had a partial backup of the data so I was quite keen to recover as much as possible from the failed device.


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Camera repair

Thu, Nov 5, 2009  in Blog using tags Uncategorized

I’ve had a Canon PowerShot S60 for several years now, but earlier this year it started exhibiting a purple banding across the top of images. It gradually got worse and worse until the banding was across enough of the picture to screw up the auto-exposure. The width of the purple band depended on what the camera was doing, and made me suspect a power supply / decoupling issue.


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Rearranging furniture

Sat, Oct 24, 2009  in Blog using tags Uncategorized

I recently rearranged the furniture in my home work area in order to make better use of space, and, because I fancied a change.


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Black box

Thu, Oct 22, 2009  in Blog using tags Electronics

A while back, you may remember that I had to put together an RS-232 level shifter for my NSLU2’s serial console. It’s been working reliably so far, despite hanging loose as a bare piece of stripboard dangling from the other end of the cable that comes out of the NSLU2.


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New website

Sun, Sep 20, 2009  in Blog using tags Uncategorized

After the best part of 10 years with a holding page, there’s now a site up at www.coolfactor.org.

That is all.


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More repairs

Sat, Aug 29, 2009  in Blog using tags Electronics

I thought it was about time to write here about my DVD player and my CD player.


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Blinking Lights of Death

Thu, Jun 4, 2009  in Blog using tags Electronics

I have a Netgear GS108 8-port gigabit ethernet switch, which died the other day. I found it working normally for a few seconds, and slowly flashing all of its lights for a few seconds, over and over again. During the flashing lights period, no packets were being passed. Naturally, this was playing havoc with my network.

After swapping in a spare switch I discovered that it was in fact a common problem with that model of switch, and that it even had a name: Blinking Lights of Death.


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IMAP, SMTP, TLS and certificates

Tue, May 19, 2009  in Blog using tags Uncategorized

A couple of years ago I had a good go at getting my Sony Ericsson phone to talk to my IMAP server over SSL. That much worked (although the IMAP client doesn’t support folders so I had to do a bit of a bodge with multiple user accounts and symlinks in cyrus to get at important folders) but I could never get authenticated SMTP over TLS to work.

Today I cracked it.


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Contactless payment card

Wed, May 13, 2009  in Blog using tags Electronics

My bank recently sent me a new debit card, which included the non-optional feature of contactless payment.


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Driving an LCD module from an FPGA

Mon, Jan 26, 2009  in Blog using tags Electronics

Some time ago I bought a Digilent Nexys 2 FPGA development board and a Digilent PmodCLS LCD module. I spent some time implementing a more or less trivial CPU in the FPGA, and various bits and pieces to aid with debugging such as a driver for the 4-digit 7-segment LED display on the board (ideal for displaying the contents of 16-bit registers) and debug LEDs and switches to select what to display. I’ve been using this primarily as an exercise in learning Verilog.


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